Score : 400 points

Problem Statement

You are given an undirected connected weighted graph with N vertices and M edges that contains neither self-loops nor double edges.

The i-th (1≤i≤M) edge connects vertex a_i and vertex b_i with a distance of c_i.

Here, a self-loop is an edge where a_i = b_i (1≤i≤M), and double edges are two edges where (a_i,b_i)=(a_j,b_j) or (a_i,b_i)=(b_j,a_j) (1≤i<j≤M).

A connected graph is a graph where there is a path between every pair of different vertices.

Find the number of the edges that are not contained in any shortest path between any pair of different vertices.

Constraints

2≤N≤100

N-1≤M≤min(N(N-1)/2,1000)

1≤a_i,b_i≤N

1≤c_i≤1000

c_i is an integer.

The given graph contains neither self-loops nor double edges.

The given graph is connected.

Input

The input is given from Standard Input in the following format:

N M
a_1 b_1 c_1
a_2 b_2 c_2
:
a_M b_M c_M

Output

Print the number of the edges in the graph that are not contained in any shortest path between any pair of different vertices.

Sample Input 1

3 3
1 2 1
1 3 1
2 3 3

Sample Output 1

1

In the given graph, the shortest paths between all pairs of different vertices are as follows:

The shortest path from vertex 1 to vertex 2 is: vertex 1 → vertex 2, with the length of 1.

The shortest path from vertex 1 to vertex 3 is: vertex 1 → vertex 3, with the length of 1.

The shortest path from vertex 2 to vertex 1 is: vertex 2 → vertex 1, with the length of 1.

The shortest path from vertex 2 to vertex 3 is: vertex 2 → vertex 1 → vertex 3, with the length of 2.

The shortest path from vertex 3 to vertex 1 is: vertex 3 → vertex 1, with the length of 1.

The shortest path from vertex 3 to vertex 2 is: vertex 3 → vertex 1 → vertex 2, with the length of 2.

Thus, the only edge that is not contained in any shortest path, is the edge of length 3 connecting vertex 2 and vertex 3, hence the output should be 1.

Sample Input 2

3 2
1 2 1
2 3 1

Sample Output 2

0

Every edge is contained in some shortest path between some pair of different vertices.


Global OOD problem IDs are disjoint from train, validation, and in-distribution test problem IDs.

Submitted source-code file size, in bytes.

Execution CPU time reported by official Project CodeNet metadata, in milliseconds.

Peak memory usage reported by official Project CodeNet metadata, in kilobytes.


Score : 300 points

Problem Statement

Snuke has a calculator. It has a display and two buttons.

Initially, the display shows an integer x.
Snuke wants to change this value into another integer y, by pressing the following two buttons some number of times in arbitrary order:

Button A: When pressed, the value on the display is incremented by 1.

Button B: When pressed, the sign of the value on the display is reversed.

Find the minimum number of times Snuke needs to press the buttons to achieve his objective.
It can be shown that the objective is always achievable regardless of the values of the integers x and y.

Constraints

x and y are integers.

|x|, |y| ≤ 10^9

x and y are different.

Input

The input is given from Standard Input in the following format:

x y

Output

Print the minimum number of times Snuke needs to press the buttons to achieve his objective.

Sample Input 1

10 20

Sample Output 1

10

Press button A ten times.

Sample Input 2

10 -10

Sample Output 2

1

Press button B once.

Sample Input 3

-10 -20

Sample Output 3

12

Press the buttons as follows:

Press button B once.

Press button A ten times.

Press button B once.


Score : 600 points

Problem Statement

A tetromino is a figure formed by joining four squares edge to edge.
We will refer to the following seven kinds of tetromino as I-, O-, T-, J-, L-, S- and Z-tetrominos, respectively:

Snuke has many tetrominos. The number of I-, O-, T-, J-, L-, S- and Z-tetrominos in his possession are a_I, a_O, a_T, a_J, a_L, a_S and a_Z, respectively.
Snuke will join K of his tetrominos to form a rectangle that is two squares tall and 2K squares wide.
Here, the following rules must be followed:

When placing each tetromino, rotation is allowed, but reflection is not.

Each square in the rectangle must be covered by exactly one tetromino.

No part of each tetromino may be outside the rectangle.

Snuke wants to form as large a rectangle as possible.
Find the maximum possible value of K.

Constraints

0≤a_I,a_O,a_T,a_J,a_L,a_S,a_Z≤10^9

a_I+a_O+a_T+a_J+a_L+a_S+a_Z≥1

Input

The input is given from Standard Input in the following format:

a_I a_O a_T a_J a_L a_S a_Z

Output

Print the maximum possible value of K. If no rectangle can be formed, print 0.

Sample Input 1

2 1 1 0 0 0 0

Sample Output 1

3

One possible way to form the largest rectangle is shown in the following figure:

Sample Input 2

0 0 10 0 0 0 0

Sample Output 2

0

No rectangle can be formed.


Score : 100 points

Problem Statement

Joisino wants to evaluate the formula "A op B".
Here, A and B are integers, and the binary operator op is either + or -.
Your task is to evaluate the formula instead of her.

Constraints

1≦A,B≦10^9

op is either + or -.

Input

The input is given from Standard Input in the following format:

A op B

Output

Evaluate the formula and print the result.

Sample Input 1

1 + 2

Sample Output 1

3

Since 1 + 2 = 3, the output should be 3.

Sample Input 2

5 - 7

Sample Output 2

-2


Score : 200 points

Problem Statement

Joisino is about to compete in the final round of a certain programming competition.
In this contest, there are N problems, numbered 1 through N.
Joisino knows that it takes her T_i seconds to solve problem i(1≦i≦N).

Also, there are M kinds of drinks offered to the contestants, numbered 1 through M.
If Joisino takes drink i(1≦i≦M), her brain will be stimulated and the time it takes for her to solve problem P_i will become X_i seconds.
It does not affect the time to solve the other problems.

A contestant is allowed to take exactly one of the drinks before the start of the contest.
For each drink, Joisino wants to know how many seconds it takes her to solve all the problems if she takes that drink.
Here, assume that the time it takes her to solve all the problems is equal to the sum of the time it takes for her to solve individual problems.
Your task is to write a program to calculate it instead of her.

Constraints

All input values are integers.

1≦N≦100

1≦T_i≦10^5

1≦M≦100

1≦P_i≦N

1≦X_i≦10^5

Input

The input is given from Standard Input in the following format:

N
T_1 T_2 ... T_N
M
P_1 X_1
P_2 X_2
:
P_M X_M

Output

For each drink, calculate how many seconds it takes Joisino to solve all the problems if she takes that drink, and print the results, one per line.

Sample Input 1

3
2 1 4
2
1 1
2 3

Sample Output 1

6
9

If Joisino takes drink 1, the time it takes her to solve each problem will be 1, 1 and 4 seconds, respectively, totaling 6 seconds.

If Joisino takes drink 2, the time it takes her to solve each problem will be 2, 3 and 4 seconds, respectively, totaling 9 seconds.

Sample Input 2

5
7 2 3 8 5
3
4 2
1 7
4 13

Sample Output 2

19
25
30


my $n=<>;chomp $n;
my $numbers=<>;chomp$numbers;
my @a=split(/ /,$numbers);
my @sorted=sort{ $a <=> $b } @a;
my@t;my $sorted;my $t;
if($n%2==0){foreach(1..$n/2) {push(@t,$_*2-1,$_*2-1);}$n=$n/2;}
		else{push(@t,0);foreach(1..($n-1)/2){push(@t,$_*2,$_*2);}$n=($n-1)/2;}

$sorted=join('/',@sorted);$t=join('/',@t);
my $answer=0;my $counter=0;
if($sorted eq $t){$answer++;while($counter<$n){$answer=$answer*2%(10**9+7);$counter++;}}
print $answer;

Score : 300 points

Problem Statement

There are N people, conveniently numbered 1 through N.
They were standing in a row yesterday, but now they are unsure of the order in which they were standing.
However, each person remembered the following fact: the absolute difference of the number of the people who were standing to the left of that person, and the number of the people who were standing to the right of that person.
According to their reports, the difference above for person i is A_i.

Based on these reports, find the number of the possible orders in which they were standing.
Since it can be extremely large, print the answer modulo 10^9+7.
Note that the reports may be incorrect and thus there may be no consistent order.
In such a case, print 0.

Constraints

1≦N≦10^5

0≦A_i≦N-1

Input

The input is given from Standard Input in the following format:

N
A_1 A_2 ... A_N

Output

Print the number of the possible orders in which they were standing, modulo 10^9+7.

Sample Input 1

5
2 4 4 0 2

Sample Output 1

4

There are four possible orders, as follows:

2,1,4,5,3

2,5,4,1,3

3,1,4,5,2

3,5,4,1,2

Sample Input 2

7
6 4 0 2 4 0 2

Sample Output 2

0

Any order would be inconsistent with the reports, thus the answer is 0.

Sample Input 3

8
7 5 1 1 7 3 5 3

Sample Output 3

16


use v6;
my $c = get().chomp;
if (($c eq 'a') or ($c eq 'e') or ($c eq 'i') or ($c eq 'o') or ($c eq 'u')) {
	say "vowel";
} else {
	say "consonant";
}

exit;

Score : 100 points

Problem Statement

Given a lowercase English letter c, determine whether it is a vowel. Here, there are five vowels in the English alphabet: a, e, i, o and u.

Constraints

c is a lowercase English letter.

Input

The input is given from Standard Input in the following format:

c

Output

If c is a vowel, print vowel. Otherwise, print consonant.

Sample Input 1

a

Sample Output 1

vowel

Since a is a vowel, print vowel.

Sample Input 2

z

Sample Output 2

consonant

Sample Input 3

s

Sample Output 3

consonant


Score : 400 points

Problem Statement

There are N cities. There are also K roads and L railways, extending between the cities.
The i-th road bidirectionally connects the p_i-th and q_i-th cities, and the i-th railway bidirectionally connects the r_i-th and s_i-th cities.
No two roads connect the same pair of cities. Similarly, no two railways connect the same pair of cities.

We will say city A and B are connected by roads if city B is reachable from city A by traversing some number of roads. Here, any city is considered to be connected to itself by roads.
We will also define connectivity by railways similarly.

For each city, find the number of the cities connected to that city by both roads and railways.

Constraints

2 ≦ N ≦ 2*10^5

1 ≦ K, L≦ 10^5

1 ≦ p_i, q_i, r_i, s_i ≦ N

p_i < q_i

r_i < s_i

When i ≠ j, (p_i, q_i) ≠ (p_j, q_j)

When i ≠ j, (r_i, s_i) ≠ (r_j, s_j)

Input

The input is given from Standard Input in the following format:

N K L
p_1 q_1
:
p_K q_K
r_1 s_1
:
r_L s_L

Output

Print N integers. The i-th of them should represent the number of the cities connected to the i-th city by both roads and railways.

Sample Input 1

4 3 1
1 2
2 3
3 4
2 3

Sample Output 1

1 2 2 1

All the four cities are connected to each other by roads.

By railways, only the second and third cities are connected. Thus, the answers for the cities are 1, 2, 2 and 1, respectively.

Sample Input 2

4 2 2
1 2
2 3
1 4
2 3

Sample Output 2

1 2 2 1

Sample Input 3

7 4 4
1 2
2 3
2 5
6 7
3 5
4 5
3 4
6 7

Sample Output 3

1 1 2 1 2 2 2


Score : 100 points

Problem Statement

Snuke is going to open a contest named "AtCoder s Contest".
Here, s is a string of length 1 or greater, where the first character is an uppercase English letter, and the second and subsequent characters are lowercase English letters.

Snuke has decided to abbreviate the name of the contest as "AxC".
Here, x is the uppercase English letter at the beginning of s.

Given the name of the contest, print the abbreviation of the name.

Constraints

The length of s is between 1 and 100, inclusive.

The first character in s is an uppercase English letter.

The second and subsequent characters in s are lowercase English letters.

Input

The input is given from Standard Input in the following format:

AtCoder s Contest

Output

Print the abbreviation of the name of the contest.

Sample Input 1

AtCoder Beginner Contest

Sample Output 1

ABC

The contest in which you are participating now.

Sample Input 2

AtCoder Snuke Contest

Sample Output 2

ASC

This contest does not actually exist.

Sample Input 3

AtCoder X Contest

Sample Output 3

AXC


Score : 200 points

Problem Statement

You are given nonnegative integers a and b (a ≤ b), and a positive integer x.
Among the integers between a and b, inclusive, how many are divisible by x?

Constraints

0 ≤ a ≤ b ≤ 10^{18}

1 ≤ x ≤ 10^{18}

Input

The input is given from Standard Input in the following format:

a b x

Output

Print the number of the integers between a and b, inclusive, that are divisible by x.

Sample Input 1

4 8 2

Sample Output 1

3

There are three integers between 4 and 8, inclusive, that are divisible by 2: 4, 6 and 8.

Sample Input 2

0 5 1

Sample Output 2

6

There are six integers between 0 and 5, inclusive, that are divisible by 1: 0, 1, 2, 3, 4 and 5.

Sample Input 3

9 9 2

Sample Output 3

0

There are no integer between 9 and 9, inclusive, that is divisible by 2.

Sample Input 4

1 1000000000000000000 3

Sample Output 4

333333333333333333

Watch out for integer overflows.


my (\a,\b,\c) = $*IN.get.split(" ")>>.Int;say b div c-(a-1) div c


Score : 500 points

Problem Statement

There is a string s of length 3 or greater.
No two neighboring characters in s are equal.

Takahashi and Aoki will play a game against each other.
The two players alternately performs the following operation, Takahashi going first:

Remove one of the characters in s, excluding both ends. However, a character cannot be removed if removal of the character would result in two neighboring equal characters in s.

The player who becomes unable to perform the operation, loses the game. Determine which player will win when the two play optimally.

Constraints

3 ≤ |s| ≤ 10^5

s consists of lowercase English letters.

No two neighboring characters in s are equal.

Input

The input is given from Standard Input in the following format:

s

Output

If Takahashi will win, print First. If Aoki will win, print Second.

Sample Input 1

aba

Sample Output 1

Second

Takahashi, who goes first, cannot perform the operation, since removal of the b, which is the only character not at either ends of s, would result in s becoming aa, with two as neighboring.

Sample Input 2

abc

Sample Output 2

First

When Takahashi removes b from s, it becomes ac.
Then, Aoki cannot perform the operation, since there is no character in s, excluding both ends.

Sample Input 3

abcab

Sample Output 3

First


Score : 500 points

Problem Statement

#nck {
width: 30px;
height: auto;
}

A cheetah and a cheater are going to play the game of Nim.
In this game they use N piles of stones.
Initially the i-th pile contains a_i stones.
The players take turns alternately, and the cheetah plays first.
In each turn, the player chooses one of the piles, and takes one or more stones from the pile.
The player who can't make a move loses.

However, before the game starts, the cheater wants to cheat a bit to make sure that he can win regardless of the moves by the cheetah.
From each pile, the cheater takes zero or one stone and eats it before the game.
In case there are multiple ways to guarantee his winning, he wants to minimize the number of stones he eats.

Compute the number of stones the cheater will eat.
In case there is no way for the cheater to win the game even with the cheating, print -1 instead.

Constraints

1 ≤ N ≤ 10^5

2 ≤ a_i ≤ 10^9

Input

The input is given from Standard Input in the following format:

N
a_1
:
a_N

Output

Print the answer.

Sample Input 1

3
2
3
4

Sample Output 1

3

The only way for the cheater to win the game is to take stones from all piles and eat them.

Sample Input 2

3
100
100
100

Sample Output 2

-1


Score : 1000 points

Problem Statement

#nck {
width: 30px;
height: auto;
}

Welcome to CODE FESTIVAL 2016!
In order to celebrate this contest, find a string s that satisfies the following conditions:

The length of s is between 1 and 5000, inclusive.

s consists of uppercase letters.

s contains exactly K occurrences of the string "FESTIVAL" as a subsequence.
In other words, there are exactly K tuples of integers (i_0, i_1, ..., i_7) such that 0 ≤ i_0 < i_1 < ... < i_7 ≤ |s|-1 and s[i_0]='F', s[i_1]='E', ..., s[i_7]='L'.

It can be proved that under the given constraints, the solution always exists.
In case there are multiple possible solutions, you can output any.

Constraints

1 ≤ K ≤ 10^{18}

Input

The input is given from Standard Input in the following format:

K

Output

Print a string that satisfies the conditions.

Sample Input 1

7

Sample Output 1

FESSSSSSSTIVAL

Sample Input 2

256

Sample Output 2

FFEESSTTIIVVAALL


Score : 100 points

Problem Statement

In an electric circuit, when two resistors R_1 and R_2 are connected in parallel, the equivalent resistance R_3 can be derived from the following formula:

\frac{1}{R_1} + \frac{1}{R_2} = \frac{1}{R_3}

Given R_1 and R_2, find R_3.

Constraints

1 \leq R_1, R_2 \leq 100

R_1 and R_2 are integers.

Input

The input is given from Standard Input in the following format:

R_1 R_2

Output

Print the value of R_3.

The output is considered correct if the absolute or relative error is at most 10^{-6}.

Sample Input 1

2 3

Sample Output 1

1.2000000000

Sample Input 2

100 99

Sample Output 2

49.7487437186


Score : 100 points

Problem Statement

Kode Festival is an anual contest where the hardest stone in the world is determined. (Kode is a Japanese word for "hardness".)

This year, 2^N stones participated. The hardness of the i-th stone is A_i.

In the contest, stones are thrown at each other in a knockout tournament.

When two stones with hardness X and Y are thrown at each other, the following will happen:

When X > Y:
The stone with hardness Y will be destroyed and eliminated.
The hardness of the stone with hardness X will become X-Y.

When X = Y:
One of the stones will be destroyed and eliminated.
The hardness of the other stone will remain the same.

When X < Y:
The stone with hardness X will be destroyed and eliminated.
The hardness of the stone with hardness Y will become Y-X.

The 2^N stones will fight in a knockout tournament as follows:

The following pairs will fight: (the 1-st stone versus the 2-nd stone), (the 3-rd stone versus the 4-th stone), ...

The following pairs will fight: (the winner of (1-st versus 2-nd) versus the winner of (3-rd versus 4-th)), (the winner of (5-th versus 6-th) versus the winner of (7-th versus 8-th)), ...

And so forth, until there is only one stone remaining.

Determine the eventual hardness of the last stone remaining.

Constraints

1 \leq N \leq 18

1 \leq A_i \leq 10^9

A_i is an integer.

Input

The input is given from Standard Input in the following format:

N
A_1
A_2
:
A_{2^N}

Output

Print the eventual hardness of the last stone remaining.

Sample Input 1

2
1
3
10
19

Sample Output 1

7

Sample Input 2

3
1
3
2
4
6
8
100
104

Sample Output 2

2


Score : 100 points

Problem Statement

Takahashi recorded his daily life for the last few days as a integer sequence of length 2N, as follows:

a_1, b_1, a_2, b_2, ... , a_N, b_N

This means that, starting from a certain time T, he was:

sleeping for exactly a_1 seconds

then awake for exactly b_1 seconds

then sleeping for exactly a_2 seconds

:

then sleeping for exactly a_N seconds

then awake for exactly b_N seconds

In this record, he waked up N times.

Takahashi is wondering how many times he waked up early during the recorded period.

Here, he is said to wake up early if he wakes up between 4:00 AM and 7:00 AM, inclusive.

If he wakes up more than once during this period, each of these awakenings is counted as waking up early.

Unfortunately, he forgot the time T.

Find the maximum possible number of times he waked up early during the recorded period.

For your information, a day consists of 86400 seconds, and the length of the period between 4:00 AM and 7:00 AM is 10800 seconds.

Constraints

1 \leq N \leq 10^5

1 \leq a_i, b_i \leq 10^5

a_i and b_i are integers.

Input

The input is given from Standard Input in the following format:

N
a_1 b_1
a_2 b_2
:
a_N b_N

Output

Print the maximum possible number of times he waked up early during the recorded period.

Sample Input 1

3
28800 57600
28800 57600
57600 28800

Sample Output 1

2

Sample Input 2

10
28800 57600
4800 9600
6000 1200
600 600
300 600
5400 600
6000 5760
6760 2880
6000 12000
9000 600

Sample Output 2

5


Score : 100 points

Problem Statement

There is a grid with H rows and W columns.

The square at the i-th row and j-th column contains a string S_{i,j} of length 5.

The rows are labeled with the numbers from 1 through H, and the columns are labeled with the uppercase English letters from A through the W-th letter of the alphabet.

Exactly one of the squares in the grid contains the string snuke. Find this square and report its location.

For example, the square at the 6-th row and 8-th column should be reported as H6.

Constraints

1≦H, W≦26

The length of S_{i,j} is 5.

S_{i,j} consists of lowercase English letters (a-z).

Exactly one of the given strings is equal to snuke.

Input

The input is given from Standard Input in the following format:

H W
S_{1,1} S_{1,2} ... S_{1,W}
S_{2,1} S_{2,2} ... S_{2,W}
:
S_{H,1} S_{H,2} ... S_{H,W}

Output

Print the labels of the row and the column of the square containing the string snuke, with no space inbetween.

Sample Input 1

15 10
snake snake snake snake snake snake snake snake snake snake
snake snake snake snake snake snake snake snake snake snake
snake snake snake snake snake snake snake snake snake snake
snake snake snake snake snake snake snake snake snake snake
snake snake snake snake snake snake snake snake snake snake
snake snake snake snake snake snake snake snuke snake snake
snake snake snake snake snake snake snake snake snake snake
snake snake snake snake snake snake snake snake snake snake
snake snake snake snake snake snake snake snake snake snake
snake snake snake snake snake snake snake snake snake snake
snake snake snake snake snake snake snake snake snake snake
snake snake snake snake snake snake snake snake snake snake
snake snake snake snake snake snake snake snake snake snake
snake snake snake snake snake snake snake snake snake snake
snake snake snake snake snake snake snake snake snake snake

Sample Output 1

H6

Sample Input 2

1 1
snuke

Sample Output 2

A1


Score : 300 points

Problem Statement

The problem set at CODE FESTIVAL 20XX Finals consists of N problems.

The score allocated to the i-th (1≦i≦N) problem is i points.

Takahashi, a contestant, is trying to score exactly N points. For that, he is deciding which problems to solve.

As problems with higher scores are harder, he wants to minimize the highest score of a problem among the ones solved by him.

Determine the set of problems that should be solved.

Constraints

1≦N≦10^7

Partial Score

200 points will be awarded for passing the test set satisfying 1≦N≦1000.

Additional 100 points will be awarded for passing the test set without additional constraints.

Input

The input is given from Standard Input in the following format:

N

Output

Among the sets of problems with the total score of N, find a set in which the highest score of a problem is minimum, then print the indices of the problems in the set in any order, one per line.

If there exists more than one such set, any of them will be accepted.

Sample Input 1

4

Sample Output 1

1
3

Solving only the 4-th problem will also result in the total score of 4 points, but solving the 1-st and 3-rd problems will lower the highest score of a solved problem.

Sample Input 2

7

Sample Output 2

1
2
4

The set \{3,4\} will also be accepted.

Sample Input 3

1

Sample Output 3

1


Max Score: $250$ Points

Problem Statement

Snuke has a very long calendar. It has a grid with $n$ rows and $7$ columns. One day, he noticed that calendar has a following regularity.

The cell at the $i$-th row and $j$-th column contains the integer $7i+j-7$.

A good sub-grid is a $3 \times 3$ sub-grid and the sum of integers in this sub-grid mod $11$ is $k$.

How many good sub-grid are there? Write a program and help him.

Input

The input is given from standard input in the following format.

$n \quad k$

Output

Print the number of good sub-grid. If there are no solution exists, print 0.

Constraints

$1 \le n \le 10^9$

$0 \le k \le 10$

Subtasks

Subtask 1 [ $150$ points ]

The testcase in the subtask satisfies $1 \le n \le 100$.

Subtask 2 [ $100$ points ]

There are no additional constraints.

Sample Input 1

7 7

Sample Output 1

2

In this case, the calendar likes this matrix.

Sun.

Mon.

Tue.

Wed.

Thu.

Fri.

Sat.

Week 1

1

2

3

4

5

6

7

Week 2

8

9

10

11

12

13

14

Week 3

15

16

17

18

19

20

21

Week 4

22

23

24

25

26

27

28

Week 5

29

30

31

32

33

34

35

Week 6

36

37

38

39

40

41

42

Week 7

43

44

45

46

47

48

49

The cell at $i$-th row and $j$-th column is denoted $(i, j)$.

If upper-left is $(1, 5)$, the sum of integers is $5+6+7+12+13+14+19+20+21=117$.

If upper-left is $(3, 2)$, the sum of integers is $16+17+18+23+24+25+30+31+32=216$.

Therefore, there are 2 good sub-grids.

Sample Input 2

6 0

Sample Output 2

2

If upper-left is $(1, 3)$ or $(4, 4)$, it is a good sub-grid.

Sample Input 3

18 10


Score : 200 points

Problem Statement

#nck {
width: 30px;
height: auto;
}

We have a grid of H rows and W columns. Initially, there is a stone in the top left cell. Shik is trying to move the stone to the bottom right cell. In each step, he can move the stone one cell to its left, up, right, or down (if such cell exists). It is possible that the stone visits a cell multiple times (including the bottom right and the top left cell).

You are given a matrix of characters a_{ij} (1 \leq i \leq H, 1 \leq j \leq W). After Shik completes all moving actions, a_{ij} is # if the stone had ever located at the i-th row and the j-th column during the process of moving. Otherwise, a_{ij} is .. Please determine whether it is possible that Shik only uses right and down moves in all steps.

Constraints

2 \leq H, W \leq 8

a_{i,j} is either # or ..

There exists a valid sequence of moves for Shik to generate the map a.

Input

The input is given from Standard Input in the following format:

H W
a_{11}a_{12}...a_{1W}
:
a_{H1}a_{H2}...a_{HW}

Output

If it is possible that Shik only uses right and down moves, print Possible. Otherwise, print Impossible.

Sample Input 1

4 5
##...
.##..
..##.
...##

Sample Output 1

Possible

The matrix can be generated by a 7-move sequence: right, down, right, down, right, down, and right.

Sample Input 2

5 3
###
..#
###
#..
###

Sample Output 2

Impossible

Sample Input 3

4 5
##...
.###.
.###.
...##

Sample Output 3

Impossible


Score : 100 points

Problem Statement

Two students of AtCoder Kindergarten are fighting over candy packs.

There are three candy packs, each of which contains a, b, and c candies, respectively.

Teacher Evi is trying to distribute the packs between the two students so that each student gets the same number of candies. Determine whether it is possible.

Note that Evi cannot take candies out of the packs, and the whole contents of each pack must be given to one of the students.

Constraints

1 ≦ a, b, c ≦ 100

Input

The input is given from Standard Input in the following format:

a b c

Output

If it is possible to distribute the packs so that each student gets the same number of candies, print Yes. Otherwise, print No.

Sample Input 1

10 30 20

Sample Output 1

Yes

Give the pack with 30 candies to one student, and give the two packs with 10 and 20 candies to the other. Then, each gets 30 candies.

Sample Input 2

30 30 100

Sample Output 2

No

In this case, the student who gets the pack with 100 candies always has more candies than the other.

Note that every pack must be given to one of them.

Sample Input 3

56 25 31

Sample Output 3

Yes


Score : 200 points

Problem Statement

There is a rectangle in the xy-plane, with its lower left corner at (0, 0) and its upper right corner at (W, H). Each of its sides is parallel to the x-axis or y-axis. Initially, the whole region within the rectangle is painted white.

Snuke plotted N points into the rectangle. The coordinate of the i-th (1 ≦ i ≦ N) point was (x_i, y_i).

Then, he created an integer sequence a of length N, and for each 1 ≦ i ≦ N, he painted some region within the rectangle black, as follows:

If a_i = 1, he painted the region satisfying x < x_i within the rectangle.

If a_i = 2, he painted the region satisfying x > x_i within the rectangle.

If a_i = 3, he painted the region satisfying y < y_i within the rectangle.

If a_i = 4, he painted the region satisfying y > y_i within the rectangle.

Find the area of the white region within the rectangle after he finished painting.

Constraints

1 ≦ W, H ≦ 100

1 ≦ N ≦ 100

0 ≦ x_i ≦ W (1 ≦ i ≦ N)

0 ≦ y_i ≦ H (1 ≦ i ≦ N)

W, H (21:32, added), x_i and y_i are integers.

a_i (1 ≦ i ≦ N) is 1, 2, 3 or 4.

Input

The input is given from Standard Input in the following format:

W H N
x_1 y_1 a_1
x_2 y_2 a_2
:
x_N y_N a_N

Output

Print the area of the white region within the rectangle after Snuke finished painting.

Sample Input 1

5 4 2
2 1 1
3 3 4

Sample Output 1

9

The figure below shows the rectangle before Snuke starts painting.

First, as (x_1, y_1) = (2, 1) and a_1 = 1, he paints the region satisfying x < 2 within the rectangle:

Then, as (x_2, y_2) = (3, 3) and a_2 = 4, he paints the region satisfying y > 3 within the rectangle:

Now, the area of the white region within the rectangle is 9.

Sample Input 2

5 4 3
2 1 1
3 3 4
1 4 2

Sample Output 2

0

It is possible that the whole region within the rectangle is painted black.

Sample Input 3

10 10 5
1 6 1
4 1 3
6 9 4
9 4 2
3 1 3

Sample Output 3

64


Score : 400 points

Problem Statement

We have a pyramid with N steps, built with blocks.
The steps are numbered 1 through N from top to bottom.
For each 1≤i≤N, step i consists of 2i-1 blocks aligned horizontally.
The pyramid is built so that the blocks at the centers of the steps are aligned vertically.

A pyramid with N=4 steps

Snuke wrote a permutation of (1, 2, ..., 2N-1) into the blocks of step N.
Then, he wrote integers into all remaining blocks, under the following rule:

The integer written into a block b must be equal to the median of the three integers written into the three blocks directly under b, or to the lower left or lower right of b.

Writing integers into the blocks

Afterwards, he erased all integers written into the blocks.
Now, he only remembers that the integer written into the block of step 1 was x.

Construct a permutation of (1, 2, ..., 2N-1) that could have been written into the blocks of step N, or declare that Snuke's memory is incorrect and such a permutation does not exist.

Constraints

2≤N≤10^5

1≤x≤2N-1

Input

The input is given from Standard Input in the following format:

N x

Output

If no permutation of (1, 2, ..., 2N-1) could have been written into the blocks of step N, print No.

Otherwise, print Yes in the first line, then print 2N-1 lines in addition.

The i-th of these 2N-1 lines should contain the i-th element of a possible permutation.

Sample Input 1

4 4

Sample Output 1

Yes
1
6
3
7
4
5
2

This case corresponds to the figure in the problem statement.

Sample Input 2

2 1

Sample Output 2

No

No matter what permutation was written into the blocks of step N, the integer written into the block of step 1 would be 2.


Score : 200 points

Problem Statement

There are K pieces of cakes.
Mr. Takahashi would like to eat one cake per day, taking K days to eat them all.

There are T types of cake, and the number of the cakes of type i (1 ≤ i ≤ T) is a_i.

Eating the same type of cake two days in a row would be no fun,
so Mr. Takahashi would like to decide the order for eating cakes that minimizes the number of days on which he has to eat the same type of cake as the day before.

Compute the minimum number of days on which the same type of cake as the previous day will be eaten.

Constraints

1 ≤ K ≤ 10000

1 ≤ T ≤ 100

1 ≤ a_i ≤ 100

a_1 + a_2 + ... + a_T = K

Input

The input is given from Standard Input in the following format:

K T
a_1 a_2 ... a_T

Output

Print the minimum number of days on which the same type of cake as the previous day will be eaten.

Sample Input 1

7 3
3 2 2

Sample Output 1

0

For example, if Mr. Takahashi eats cakes in the order of 2, 1, 2, 3, 1, 3, 1, he can avoid eating the same type of cake as the previous day.

Sample Input 2

6 3
1 4 1

Sample Output 2

1

There are 6 cakes.
For example, if Mr. Takahashi eats cakes in the order of 2, 3, 2, 2, 1, 2, he has to eat the same type of cake (i.e., type 2) as the previous day only on the fourth day.
Since this is the minimum number, the answer is 1.

Sample Input 3

100 1
100

Sample Output 3

99

Since Mr. Takahashi has only one type of cake, he has no choice but to eat the same type of cake as the previous day from the second day and after.


Score : 100 points

Problem Statement

AtCoDeer the deer recently bought three paint cans.
The color of the one he bought two days ago is a, the color of the one he bought yesterday is b, and the color of the one he bought today is c.
Here, the color of each paint can is represented by an integer between 1 and 100, inclusive.

Since he is forgetful, he might have bought more than one paint can in the same color.
Count the number of different kinds of colors of these paint cans and tell him.

Constraints

1≦a,b,c≦100

Input

The input is given from Standard Input in the following format:

a b c

Output

Print the number of different kinds of colors of the paint cans.

Sample Input 1

3 1 4

Sample Output 1

3

Three different colors: 1, 3, and 4.

Sample Input 2

3 3 33

Sample Output 2

2

Two different colors: 3 and 33.


my %seen;
print scalar(grep { chomp; ! $seen{$_}++ } split(/ /, <STDIN>));


Score : 200 points

Problem Statement

There are N balls placed in a row.
AtCoDeer the deer is painting each of these in one of the K colors of his paint cans.
For aesthetic reasons, any two adjacent balls must be painted in different colors.

Find the number of the possible ways to paint the balls.

Constraints

1≦N≦1000

2≦K≦1000

The correct answer is at most 2^{31}-1.

Input

The input is given from Standard Input in the following format:

N K

Output

Print the number of the possible ways to paint the balls.

Sample Input 1

2 2

Sample Output 1

2

We will denote the colors by 0 and 1. There are two possible ways: we can either paint the left ball in color 0 and the right ball in color 1, or paint the left in color 1 and the right in color 0.

Sample Input 2

1 10

Sample Output 2

10

Since there is only one ball, we can use any of the ten colors to paint it. Thus, the answer is ten.


Score : 300 points

Problem Statement

AtCoDeer the deer is seeing a quick report of election results on TV.
Two candidates are standing for the election: Takahashi and Aoki.
The report shows the ratio of the current numbers of votes the two candidates have obtained, but not the actual numbers of votes.
AtCoDeer has checked the report N times, and when he checked it for the i-th (1≦i≦N) time, the ratio was T_i:A_i.
It is known that each candidate had at least one vote when he checked the report for the first time.

Find the minimum possible total number of votes obtained by the two candidates when he checked the report for the N-th time.
It can be assumed that the number of votes obtained by each candidate never decreases.

Constraints

1≦N≦1000

1≦T_i,A_i≦1000 (1≦i≦N)

T_i and A_i (1≦i≦N) are coprime.

It is guaranteed that the correct answer is at most 10^{18}.

Input

The input is given from Standard Input in the following format:

N
T_1 A_1
T_2 A_2
:
T_N A_N

Output

Print the minimum possible total number of votes obtained by Takahashi and Aoki when AtCoDeer checked the report for the N-th time.

Sample Input 1

3
2 3
1 1
3 2

Sample Output 1

10

When the numbers of votes obtained by the two candidates change as 2,3 → 3,3 → 6,4, the total number of votes at the end is 10, which is the minimum possible number.

Sample Input 2

4
1 1
1 1
1 5
1 100

Sample Output 2

101

It is possible that neither candidate obtained a vote between the moment when he checked the report, and the moment when he checked it for the next time.

Sample Input 3

5
3 10
48 17
31 199
231 23
3 2

Sample Output 3

6930


my $str = <STDIN>;
chomp $str;
my ($N, $A, $B) = split(/\s/,$str);

$str = <STDIN>;
chomp $str;

my $i = 0, $j = 0;
my $a = 0, $b = 0;

foreach (split//, $str) {
    if ($_ ne "c" && $i + $j < $A + $B) {
        if ($_ eq "a") {
            print "Yes\n";
            $i++;
            next;
        }
        if ($_ eq "b" && $j < $B) {
            print "Yes\n";
            $j++;
            next;
        }
    }
    print "No\n";
}

Score : 100 points

Problem Statement

CODE FESTIVAL 2016 is going to be held. For the occasion, Mr. Takahashi decided to make a signboard.

He intended to write CODEFESTIVAL2016 on it, but he mistakenly wrote a different string S. Fortunately, the string he wrote was the correct length.

So Mr. Takahashi decided to perform an operation that replaces a certain character with another in the minimum number of iterations, changing the string to CODEFESTIVAL2016.

Find the minimum number of iterations for the rewrite operation.

Constraints

S is 16 characters long.

S consists of uppercase and lowercase alphabet letters and numerals.

Input

Inputs are provided from Standard Input in the following form.

S

Output

Output an integer representing the minimum number of iterations needed for the rewrite operation.

Sample Input 1

C0DEFESTIVAL2O16

Sample Output 1

2

The second character 0 must be changed to O and the 14th character O changed to 0.

Sample Input 2

FESTIVAL2016CODE

Sample Output 2

16


Score : 500 points

Problem Statement

On an xy plane, in an area satisfying 0 ≤ x ≤ W, 0 ≤ y ≤ H, there is one house at each and every point where both x and y are integers.

There are unpaved roads between every pair of points for which either the x coordinates are equal and the difference between the y coordinates is 1, or the y coordinates are equal and the difference between the x coordinates is 1.

The cost of paving a road between houses on coordinates (i,j) and (i+1,j) is p_i for any value of j, while the cost of paving a road between houses on coordinates (i,j) and (i,j+1) is q_j for any value of i.

Mr. Takahashi wants to pave some of these roads and be able to travel between any two houses on paved roads only. Find the solution with the minimum total cost.

Constraints

1 ≦ W,H ≦ 10^5

1 ≦ p_i ≦ 10^8(0 ≦ i ≦ W-1)

1 ≦ q_j ≦ 10^8(0 ≦ j ≦ H-1)

p_i (0 ≦ i ≦ W−1) is an integer.

q_j (0 ≦ j ≦ H−1) is an integer.

Input

Inputs are provided from Standard Input in the following form.

W H
p_0
:
p_{W-1}
q_0
:
q_{H-1}

Output

Output an integer representing the minimum total cost.

Sample Input 1

2 2
3
5
2
7

Sample Output 1

29

It is enough to pave the following eight roads.

Road connecting houses at (0,0) and (0,1)

Road connecting houses at (0,1) and (1,1)

Road connecting houses at (0,2) and (1,2)

Road connecting houses at (1,0) and (1,1)

Road connecting houses at (1,0) and (2,0)

Road connecting houses at (1,1) and (1,2)

Road connecting houses at (1,2) and (2,2)

Road connecting houses at (2,0) and (2,1)

Sample Input 2

4 3
2
4
8
1
2
9
3

Sample Output 2

60


Score : 700 points

Problem Statement

N people are waiting in a single line in front of the Takahashi Store. The cash on hand of the i-th person from the front of the line is a positive integer A_i.

Mr. Takahashi, the shop owner, has decided on the following scheme: He picks a product, sets a positive integer P indicating its price, and shows this product to customers in order, starting from the front of the line. This step is repeated as described below.

At each step, when a product is shown to a customer, if price P is equal to or less than the cash held by that customer at the time, the customer buys the product and Mr. Takahashi ends the current step. That is, the cash held by the first customer in line with cash equal to or greater than P decreases by P, and the next step begins.

Mr. Takahashi can set the value of positive integer P independently at each step.

He would like to sell as many products as possible. However, if a customer were to end up with 0 cash on hand after a purchase, that person would not have the fare to go home. Customers not being able to go home would be a problem for Mr. Takahashi, so he does not want anyone to end up with 0 cash.

Help out Mr. Takahashi by writing a program that determines the maximum number of products he can sell, when the initial cash in possession of each customer is given.

Constraints

1 ≦ | N | ≦ 100000

1 ≦ A_i ≦ 10^9(1 ≦ i ≦ N)

All inputs are integers.

Input

Inputs are provided from Standard Inputs in the following form.

N
A_1
:
A_N

Output

Output an integer representing the maximum number of products Mr. Takahashi can sell.

Sample Input 1

3
3
2
5

Sample Output 1

3

As values of P, select in order 1, 4, 1.

Sample Input 2

15
3
1
4
1
5
9
2
6
5
3
5
8
9
7
9

Sample Output 2

18


Score : 66 points

Problem Statement

Summer vacation ended at last and the second semester has begun.
You, a Kyoto University student, came to university and heard a rumor that somebody will barricade the entrance of your classroom.
The barricade will be built just before the start of the A-th class and removed by Kyoto University students just before the start of the B-th class.
All the classes conducted when the barricade is blocking the entrance will be cancelled and you will not be able to attend them.
Today you take N classes and class i is conducted in the t_i-th period.
You take at most one class in each period.
Find the number of classes you can attend.

Constraints

1 \leq N \leq 1000

1 \leq A < B \leq 10^9

1 \leq t_i \leq 10^9

All t_i values are distinct.

Input

N, A and B are given on the first line and t_i is given on the (i+1)-th line.

N A B
t1
:
tN

Output

Print the number of classes you can attend.

Sample Input 1

5 5 9
4
3
6
9
1

Sample Output 1

4

You can not only attend the third class.

Sample Input 2

5 4 9
5
6
7
8
9

Sample Output 2

1

You can only attend the fifth class.

Sample Input 3

4 3 6
9
6
8
1

Sample Output 3

4

You can attend all the classes.

Sample Input 4

2 1 2
1
2

Sample Output 4

1

You can not attend the first class, but can attend the second.


Score : 100 points

Problem Statement

Kyoto University Programming Contest is a programming contest voluntarily held by some Kyoto University students.
This contest is abbreviated as Kyoto University Programming Contest and called KUPC.

source: Kyoto University Programming Contest Information

The problem-preparing committee met to hold this year's KUPC and N problems were proposed there.
The problems are numbered from 1 to N and the name of i-th problem is P_i.
However, since they proposed too many problems, they decided to divide them into some sets for several contests.

They decided to divide this year's KUPC into several KUPCs by dividing problems under the following conditions.

One KUPC provides K problems.

Each problem appears at most once among all the KUPCs.

All the first letters of the problem names in one KUPC must be different.

You, one of the committee members, want to hold as many KUPCs as possible.
Write a program to find the maximum number of KUPCs that can be held this year.

Constraints

1 \leq N \leq 10^4

1 \leq K \leq 26

1 \leq |P_i| \leq 10

All characters in P_i are capital letters.

Note that, for each i and j (1 \leq i < j \leq N),
P_i \neq P_j are not necessarily satisfied.

Input

The input is given from Standard Input in the following format:

N K
P_1
:
P_N

Output

Print the maximum number of KUPCs that can be held on one line.

Sample Input 1

9 3
APPLE
ANT
ATCODER
BLOCK
BULL
BOSS
CAT
DOG
EGG

For example, three KUPCs can be held by dividing the problems as follows.

First: APPLE, BLOCK, CAT

Second: ANT, BULL, DOG

Third: ATCODER, BOSS, EGG

Sample Output 1

3

Sample Input 2

3 2
KU
KYOUDAI
KYOTOUNIV

Sample Output 2

0

No KUPC can be held.


#!/usr/bin/perl
use strict;
use warnings FATAL => 'all';
use List::Util qw( max );

my $string = <>;
chomp $string;

my $count = 0;
foreach my $c (split //, $string)
{
    if ($c eq 'T')
    {
        $count++;
    }
    else
    {
        last;
    }
}

my $count2 = 0;
foreach my $c (split //, reverse($string))
{
    if ($c eq 'S')
    {
        $count2++;
    }
    else
    {
        last;
    }
}
#print reverse($string);
#print " $count $count2\n";
print max($count, $count2) * 2;

Score : 300 points

Problem Statement

We have a string X, which has an even number of characters. Half the characters are S, and the other half are T.

Takahashi, who hates the string ST, will perform the following operation 10^{10000} times:

Among the occurrences of ST in X as (contiguous) substrings, remove the leftmost one. If there is no occurrence, do nothing.

Find the eventual length of X.

Constraints

2 ≦ |X| ≦ 200,000

The length of X is even.

Half the characters in X are S, and the other half are T.

Partial Scores

In test cases worth 200 points, |X| ≦ 200.

Input

The input is given from Standard Input in the following format:

X

Output

Print the eventual length of X.

Sample Input 1

TSTTSS

Sample Output 1

4

In the 1-st operation, the 2-nd and 3-rd characters of TSTTSS are removed.
X becomes TTSS, and since it does not contain ST anymore, nothing is done in the remaining 10^{10000}-1 operations.
Thus, the answer is 4.

Sample Input 2

SSTTST

Sample Output 2

0

X will eventually become an empty string: SSTTST ⇒ STST ⇒ ST ⇒ ``.

Sample Input 3

TSSTTTSS

Sample Output 3

4

X will become: TSSTTTSS ⇒ TSTTSS ⇒ TTSS.


Score : 700 points

Problem Statement

Aoki loves numerical sequences and trees.

One day, Takahashi gave him an integer sequence of length N, a_1, a_2, ..., a_N, which made him want to construct a tree.

Aoki wants to construct a tree with N vertices numbered 1 through N, such that for each i = 1,2,...,N, the distance between vertex i and the farthest vertex from it is a_i, assuming that the length of each edge is 1.

Determine whether such a tree exists.

Constraints

2 ≦ N ≦ 100

1 ≦ a_i ≦ N-1

Input

The input is given from Standard Input in the following format:

N
a_1 a_2 ... a_N

Output

If there exists a tree that satisfies the condition, print Possible. Otherwise, print Impossible.

Sample Input 1

5
3 2 2 3 3

Sample Output 1

Possible

The diagram above shows an example of a tree that satisfies the conditions. The red arrows show paths from each vertex to the farthest vertex from it.

Sample Input 2

3
1 1 2

Sample Output 2

Impossible

Sample Input 3

10
1 2 2 2 2 2 2 2 2 2

Sample Output 3

Possible

Sample Input 4

10
1 1 2 2 2 2 2 2 2 2

Sample Output 4

Impossible

Sample Input 5

6
1 1 1 1 1 5

Sample Output 5

Impossible

Sample Input 6

5
4 3 2 3 4

Sample Output 6

Possible


Score : 100 points

Problem Statement

This contest is CODE FESTIVAL.
However, Mr. Takahashi always writes it CODEFESTIVAL, omitting the single space between CODE and FESTIVAL.

So he has decided to make a program that puts the single space he omitted.

You are given a string s with 12 letters.
Output the string putting a single space between the first 4 letters and last 8 letters in the string s.

Constraints

s contains exactly 12 letters.

All letters in s are uppercase English letters.

Input

The input is given from Standard Input in the following format:

s

Output

Print the string putting a single space between the first 4 letters and last 8 letters in the string s.
Put a line break at the end.

Sample Input 1

CODEFESTIVAL

Sample Output 1

CODE FESTIVAL

Putting a single space between the first 4 letters and last 8 letters in CODEFESTIVAL makes it CODE FESTIVAL.

Sample Input 2

POSTGRADUATE

Sample Output 2

POST GRADUATE

Sample Input 3

ABCDEFGHIJKL

Sample Output 3

ABCD EFGHIJKL


Score : 400 points

Problem Statement

Mr. Takahashi has a string s consisting of lowercase English letters.
He repeats the following operation on s exactly K times.

Choose an arbitrary letter on s and change that letter to the next alphabet. Note that the next letter of z is a.

For example, if you perform an operation for the second letter on aaz, aaz becomes abz.
If you then perform an operation for the third letter on abz, abz becomes aba.

Mr. Takahashi wants to have the lexicographically smallest string after performing exactly K operations on s.
Find the such string.

Constraints

1≤|s|≤10^5

All letters in s are lowercase English letters.

1≤K≤10^9

Input

The input is given from Standard Input in the following format:

s
K

Output

Print the lexicographically smallest string after performing exactly K operations on s.

Sample Input 1

xyz
4

Sample Output 1

aya

For example, you can perform the following operations: xyz, yyz, zyz, ayz, aya.

Sample Input 2

a
25

Sample Output 2

z

You have to perform exactly K operations.

Sample Input 3

codefestival
100

Sample Output 3

aaaafeaaivap


Score : 100 points

Problem Statement

You are given a trapezoid. The lengths of its upper base, lower base, and height are a, b, and h, respectively.

An example of a trapezoid

Find the area of this trapezoid.

Constraints

1≦a≦100

1≦b≦100

1≦h≦100

All input values are integers.

h is even.

Input

The input is given from Standard Input in the following format:

a
b
h

Output

Print the area of the given trapezoid. It is guaranteed that the area is an integer.

Sample Input 1

3
4
2

Sample Output 1

7

When the lengths of the upper base, lower base, and height are 3, 4, and 2, respectively, the area of the trapezoid is (3+4)×2/2 = 7.

Sample Input 2

4
4
4

Sample Output 2

16

In this case, a parallelogram is given, which is also a trapezoid.


use strict;
use warnings;
use utf8;

my $a = <STDIN>;
my $b = <STDIN>;
my $h = <STDIN>;
chomp($a);
chomp($b);
chomp($h);
my $ans = ($a + $b) * $h / 2;
print $ans;


#!perl
use strict;
use warnings;
use utf8;
use feature qw/say/;

my $S_a = <STDIN>;
my $S_b = <STDIN>;
my $S_c = <STDIN>;

chomp $S_a;
chomp $S_b;
chomp $S_c;

my $cards = +{};
$cards->{a} = [split(//, $S_a)];
$cards->{b} = [split(//, $S_b)];
$cards->{c} = [split(//, $S_c)];

my $current_player = 'a';
while ( scalar @{ $cards->{$current_player} } > 0) {
    $current_player = shift $cards->{$current_player};
}

say $current_player;


Score : 200 points

Problem Statement

Alice, Bob and Charlie are playing Card Game for Three, as below:

At first, each of the three players has a deck consisting of some number of cards. Each card has a letter a, b or c written on it. The orders of the cards in the decks cannot be rearranged.

The players take turns. Alice goes first.

If the current player's deck contains at least one card, discard the top card in the deck. Then, the player whose name begins with the letter on the discarded card, takes the next turn. (For example, if the card says a, Alice takes the next turn.)

If the current player's deck is empty, the game ends and the current player wins the game.

You are given the initial decks of the players.
More specifically, you are given three strings S_A, S_B and S_C. The i-th (1≦i≦|S_A|) letter in S_A is the letter on the i-th card in Alice's initial deck. S_B and S_C describes Bob's and Charlie's initial decks in the same way.

Determine the winner of the game.

Constraints

1≦|S_A|≦100

1≦|S_B|≦100

1≦|S_C|≦100

Each letter in S_A, S_B, S_C is a, b or c.

Input

The input is given from Standard Input in the following format:

S_A
S_B
S_C

Output

If Alice will win, print A. If Bob will win, print B. If Charlie will win, print C.

Sample Input 1

aca
accc
ca

Sample Output 1

A

The game will progress as below:

Alice discards the top card in her deck, a. Alice takes the next turn.

Alice discards the top card in her deck, c. Charlie takes the next turn.

Charlie discards the top card in his deck, c. Charlie takes the next turn.

Charlie discards the top card in his deck, a. Alice takes the next turn.

Alice discards the top card in her deck, a. Alice takes the next turn.

Alice's deck is empty. The game ends and Alice wins the game.

Sample Input 2

abcb
aacb
bccc

Sample Output 2

C


use v5.18;
use warnings;
use Data::Dumper;

sub get_str {
  chomp(my $str = <>);
  $str;
}

my %cards = map { $_ => [ split //, get_str ] } "a" .. "c";

my $winner = rec("a");
say uc $winner;

sub rec {
  my $now = shift;
  my $next = shift @{ $cards{$now} };
  return $now unless $next;
  rec($next);
}


#!/usr/bin/perl -w

chomp(@lines = <>);
%cards = (
    a => [split //, shift @lines],
    b => [split //, shift @lines],
    c => [split //, shift @lines]
);

my $player = 'a';
while (1) {
    my $card = shift @{$cards{$player}};
    if ($card) {

        $player = $card;
    } else {
        last;
    }
}

print uc $player;


Score : 300 points

Problem Statement

You are given a string S consisting of digits between 1 and 9, inclusive.
You can insert the letter + into some of the positions (possibly none) between two letters in this string.
Here, + must not occur consecutively after insertion.

All strings that can be obtained in this way can be evaluated as formulas.

Evaluate all possible formulas, and print the sum of the results.

Constraints

1 \leq |S| \leq 10

All letters in S are digits between 1 and 9, inclusive.

Input

The input is given from Standard Input in the following format:

S

Output

Print the sum of the evaluated value over all possible formulas.

Sample Input 1

125

Sample Output 1

176

There are 4 formulas that can be obtained: 125, 1+25, 12+5 and 1+2+5. When each formula is evaluated,

125

1+25=26

12+5=17

1+2+5=8

Thus, the sum is 125+26+17+8=176.

Sample Input 2

9999999999

Sample Output 2

12656242944


Score : 400 points

Problem Statement

We have a grid with H rows and W columns. At first, all cells were painted white.

Snuke painted N of these cells. The i-th ( 1 \leq i \leq N ) cell he painted is the cell at the a_i-th row and b_i-th column.

Compute the following:

For each integer j ( 0 \leq j \leq 9 ), how many subrectangles of size 3×3 of the grid contains exactly j black cells, after Snuke painted N cells?

Constraints

3 \leq H \leq 10^9

3 \leq W \leq 10^9

0 \leq N \leq min(10^5,H×W)

1 \leq a_i \leq H (1 \leq i \leq N)

1 \leq b_i \leq W (1 \leq i \leq N)

(a_i, b_i) \neq (a_j, b_j) (i \neq j)

Input

The input is given from Standard Input in the following format:

H W N
a_1 b_1
:
a_N b_N

Output

Print 10 lines.
The (j+1)-th ( 0 \leq j \leq 9 ) line should contain the number of the subrectangles of size 3×3 of the grid that contains exactly j black cells.

Sample Input 1

4 5 8
1 1
1 4
1 5
2 3
3 1
3 2
3 4
4 4

Sample Output 1

0
0
0
2
4
0
0
0
0
0

There are six subrectangles of size 3×3. Two of them contain three black cells each, and the remaining four contain four black cells each.

Sample Input 2

10 10 20
1 1
1 4
1 9
2 5
3 10
4 2
4 7
5 9
6 4
6 6
6 7
7 1
7 3
7 7
8 1
8 5
8 10
9 2
10 4
10 9

Sample Output 2

4
26
22
10
2
0
0
0
0
0

Sample Input 3

1000000000 1000000000 0

Sample Output 3

999999996000000004
0
0
0
0
0
0
0
0
0


use strict;
use warnings;

my $stdin = <STDIN>;
chomp($stdin);
my @sides = split(/ /, $stdin);
print is_include_even(\@sides) ? 0 : count_diff_block(\@sides), "\n";

sub count_diff_block{
  my ($sides) = @_;
  @$sides = sort {$a <=> $b} @$sides;
  my $diff_num = $sides->[0] * $sides->[1];
  return $diff_num;
}

sub is_include_even{
  my ($array) = @_;
  for my $var (@$array) {
    return 1 if $var % 2 == 0;
  }
  return 0;
}

Score : 200 points

Problem Statement

We have a rectangular parallelepiped of size A×B×C, built with blocks of size 1×1×1. Snuke will paint each of the A×B×C blocks either red or blue, so that:

There is at least one red block and at least one blue block.

The union of all red blocks forms a rectangular parallelepiped.

The union of all blue blocks forms a rectangular parallelepiped.

Snuke wants to minimize the difference between the number of red blocks and the number of blue blocks. Find the minimum possible difference.

Constraints

2≤A,B,C≤10^9

Input

The input is given from Standard Input in the following format:

A B C

Output

Print the minimum possible difference between the number of red blocks and the number of blue blocks.

Sample Input 1

3 3 3

Sample Output 1

9

For example, Snuke can paint the blocks as shown in the diagram below.
There are 9 red blocks and 18 blue blocks, thus the difference is 9.

Sample Input 2

2 2 4

Sample Output 2

0

For example, Snuke can paint the blocks as shown in the diagram below.
There are 8 red blocks and 8 blue blocks, thus the difference is 0.

Sample Input 3

5 3 5

Sample Output 3

15

For example, Snuke can paint the blocks as shown in the diagram below.
There are 45 red blocks and 30 blue blocks, thus the difference is 9.


Score : 400 points

Problem Statement

Snuke lives in another world, where slimes are real creatures and kept by some people.
Slimes come in N colors. Those colors are conveniently numbered 1 through N.
Snuke currently has no slime. His objective is to have slimes of all the colors together.

Snuke can perform the following two actions:

Select a color i (1≤i≤N), such that he does not currently have a slime in color i, and catch a slime in color i. This action takes him a_i seconds.

Cast a spell, which changes the color of all the slimes that he currently has. The color of a slime in color i (1≤i≤N-1) will become color i+1, and the color of a slime in color N will become color 1. This action takes him x seconds.

Find the minimum time that Snuke needs to have slimes in all N colors.

Constraints

2≤N≤2,000

a_i are integers.

1≤a_i≤10^9

x is an integer.

1≤x≤10^9

Input

The input is given from Standard Input in the following format:

N x
a_1 a_2 ... a_N

Output

Find the minimum time that Snuke needs to have slimes in all N colors.

Sample Input 1

2 10
1 100

Sample Output 1

12

Snuke can act as follows:

Catch a slime in color 1. This takes 1 second.

Cast the spell. The color of the slime changes: 1 → 2. This takes 10 seconds.

Catch a slime in color 1. This takes 1 second.

Sample Input 2

3 10
100 1 100

Sample Output 2

23

Snuke can act as follows:

Catch a slime in color 2. This takes 1 second.

Cast the spell. The color of the slime changes: 2 → 3. This takes 10 seconds.

Catch a slime in color 2. This takes 1 second.

Cast the soell. The color of each slime changes: 3 → 1, 2 → 3. This takes 10 seconds.

Catch a slime in color 2. This takes 1 second.

Sample Input 3

4 10
1 2 3 4

Sample Output 3

10

Snuke can act as follows:

Catch a slime in color 1. This takes 1 second.

Catch a slime in color 2. This takes 2 seconds.

Catch a slime in color 3. This takes 3 seconds.

Catch a slime in color 4. This takes 4 seconds.


use v6;
my $n = get().chomp;
my $k = get().chomp;
my $x = get().chomp;
my $y = get().chomp;

if ($k <= $n) {
       	say $k * $x + ($n - $k) * $y;
} else {
       	say $n * $x;
}

exit;

Score : 100 points

Problem Statement

There is a hotel with the following accommodation fee:

X yen (the currency of Japan) per night, for the first K nights

Y yen per night, for the (K+1)-th and subsequent nights

Tak is staying at this hotel for N consecutive nights.
Find his total accommodation fee.

Constraints

1 \leq N, K \leq 10000

1 \leq Y < X \leq 10000

N,\,K,\,X,\,Y are integers.

Input

The input is given from Standard Input in the following format:

N
K
X
Y

Output

Print Tak's total accommodation fee.

Sample Input 1

5
3
10000
9000

Sample Output 1

48000

The accommodation fee is as follows:

10000 yen for the 1-st night

10000 yen for the 2-nd night

10000 yen for the 3-rd night

9000 yen for the 4-th night

9000 yen for the 5-th night

Thus, the total is 48000 yen.

Sample Input 2

2
3
10000
9000

Sample Output 2

20000


my Int $max-days = $*IN.get.Int;
my Int $former-days = $*IN.get.Int;
my Int $former-price = $*IN.get.Int;
my Int $latter-price = $*IN.get.Int;

say $former-price * ($former-days,$max-days).min + $latter-price * ($max-days - $former-days <= 0 ?? 0 !! $max-days - $former-days)


Score : 200 points

Problem Statement

Let w be a string consisting of lowercase letters.
We will call w beautiful if the following condition is satisfied:

Each lowercase letter of the English alphabet occurs even number of times in w.

You are given the string w. Determine if w is beautiful.

Constraints

1 \leq |w| \leq 100

w consists of lowercase letters (a-z).

Input

The input is given from Standard Input in the following format:

w

Output

Print Yes if w is beautiful. Print No otherwise.

Sample Input 1

abaccaba

Sample Output 1

Yes

a occurs four times, b occurs twice, c occurs twice and the other letters occur zero times.

Sample Input 2

hthth

Sample Output 2

No


my $s = glob<>;
for my $c ( 'a' .. 'z' ) {
    length( $s ) % 2 and print 'No' and exit;
    $s =~ tr/$c//;
}
print 'Yes'


Score : 300 points

Problem Statement

Tak has N cards. On the i-th (1 \leq i \leq N) card is written an integer x_i.
He is selecting one or more cards from these N cards, so that the average of the integers written on the selected cards is exactly A.
In how many ways can he make his selection?

Constraints

1 \leq N \leq 50

1 \leq A \leq 50

1 \leq x_i \leq 50

N,\,A,\,x_i are integers.

Partial Score

200 points will be awarded for passing the test set satisfying 1 \leq N \leq 16.

Input

The input is given from Standard Input in the following format:

N A
x_1 x_2 ... x_N

Output

Print the number of ways to select cards such that the average of the written integers is exactly A.

Sample Input 1

4 8
7 9 8 9

Sample Output 1

5

The following are the 5 ways to select cards such that the average is 8:

Select the 3-rd card.

Select the 1-st and 2-nd cards.

Select the 1-st and 4-th cards.

Select the 1-st, 2-nd and 3-rd cards.

Select the 1-st, 3-rd and 4-th cards.

Sample Input 2

3 8
6 6 9

Sample Output 2

0

Sample Input 3

8 5
3 6 2 8 7 6 5 9

Sample Output 3

19

Sample Input 4

33 3
3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3

Sample Output 4

8589934591

The answer may not fit into a 32-bit integer.


Score : 200 points

Problem Statement

Snuke lives on an infinite two-dimensional plane. He is going on an N-day trip.
At the beginning of Day 1, he is at home. His plan is described in a string S of length N.
On Day i(1 ≦ i ≦ N), he will travel a positive distance in the following direction:

North if the i-th letter of S is N

West if the i-th letter of S is W

South if the i-th letter of S is S

East if the i-th letter of S is E

He has not decided each day's travel distance. Determine whether it is possible to set each day's travel distance so that he will be back at home at the end of Day N.

Constraints

1 ≦ | S | ≦ 1000

S consists of the letters N, W, S, E.

Input

The input is given from Standard Input in the following format:

S

Output

Print Yes if it is possible to set each day's travel distance so that he will be back at home at the end of Day N. Otherwise, print No.

Sample Input 1

SENW

Sample Output 1

Yes

If Snuke travels a distance of 1 on each day, he will be back at home at the end of day 4.

Sample Input 2

NSNNSNSN

Sample Output 2

Yes

Sample Input 3

NNEW

Sample Output 3

No

Sample Input 4

W

Sample Output 4

No


Score : 600 points

Problem Statement

Snuke got an integer sequence of length N from his mother, as a birthday present. The i-th (1 ≦ i ≦ N) element of the sequence is a_i. The elements are pairwise distinct.
He is sorting this sequence in increasing order.
With supernatural power, he can perform the following two operations on the sequence in any order:

Operation 1: choose 2 consecutive elements, then reverse the order of those elements.

Operation 2: choose 3 consecutive elements, then reverse the order of those elements.

Snuke likes Operation 2, but not Operation 1. Find the minimum number of Operation 1 that he has to perform in order to sort the sequence in increasing order.

Constraints

1 ≦ N ≦ 10^5

0 ≦ A_i ≦ 10^9

If i ≠ j, then A_i ≠ A_j.

All input values are integers.

Input

The input is given from Standard Input in the following format:

N
A_1
:
A_N

Output

Print the minimum number of times Operation 1 that Snuke has to perform.

Sample Input 1

4
2
4
3
1

Sample Output 1

1

The given sequence can be sorted as follows:

First, reverse the order of the last three elements. The sequence is now: 2,1,3,4.

Then, reverse the order of the first two elements. The sequence is now: 1,2,3,4.

In this sequence of operations, Operation 1 is performed once. It is not possible to sort the sequence with less number of Operation 1, thus the answer is 1.

Sample Input 2

5
10
8
5
3
2

Sample Output 2

0


Score : 1100 points

Problem Statement

Snuke got positive integers s_1,...,s_N from his mother, as a birthday present. There may be duplicate elements.

He will circle some of these N integers. Since he dislikes cubic numbers, he wants to ensure that if both s_i and s_j (i ≠ j) are circled, the product s_is_j is not cubic. For example, when s_1=1,s_2=1,s_3=2,s_4=4, it is not possible to circle both s_1 and s_2 at the same time. It is not possible to circle both s_3 and s_4 at the same time, either.

Find the maximum number of integers that Snuke can circle.

Constraints

1 ≦ N ≦ 10^5

1 ≦ s_i ≦ 10^{10}

All input values are integers.

Input

The input is given from Standard Input in the following format:

N
s_1
:
s_N

Output

Print the maximum number of integers that Snuke can circle.

Sample Input 1

8
1
2
3
4
5
6
7
8

Sample Output 1

6

Snuke can circle 1,2,3,5,6,7.

Sample Input 2

6
2
4
8
16
32
64

Sample Output 2

3

Sample Input 3

10
1
10
100
1000000007
10000000000
1000000009
999999999
999
999
999

Sample Output 3

9


use strict;
my $N = <STDIN>;
my $line = <STDIN>;
my @a=split ' ',$line;

my $mean=0;
for(my $i=0;$i<$N;$i++){ $mean += $a[$i]; }

$mean = int($mean/$N);

my @cost;
my $l=0;
my $plus=$mean;
my $minus=$mean;
my $tempM=$mean;
my $tempP=$mean;

while($l<3){
  my $k=0;
  my $up=0;
  my $down=0;
  while($k<$N){
    $up += ($a[$k]-$tempP)*($a[$k]-$tempP);
    $k++;
  }
  my $k=0;
  while($k<$N){
    $down += ($a[$k]-$tempM)*($a[$k]-$tempM);
    $k++;
  }
  push @cost,$up;
  push @cost,$down;
  $tempP++;
  $tempM--;
  $l++;
}

@cost = sort{$a<=>$b}@cost;

print"$cost[0]\n";

Score : 200 points

Problem Statement

Evi has N integers a_1,a_2,..,a_N. His objective is to have N equal integers by transforming some of them.

He may transform each integer at most once. Transforming an integer x into another integer y costs him (x-y)^2 dollars. Even if a_i=a_j (i≠j), he has to pay the cost separately for transforming each of them (See Sample 2).

Find the minimum total cost to achieve his objective.

Constraints

1≦N≦100

-100≦a_i≦100

Input

The input is given from Standard Input in the following format:

N
a_1 a_2 ... a_N

Output

Print the minimum total cost to achieve Evi's objective.

Sample Input 1

2
4 8

Sample Output 1

8

Transforming the both into 6s will cost (4-6)^2+(8-6)^2=8 dollars, which is the minimum.

Sample Input 2

3
1 1 3

Sample Output 2

3

Transforming the all into 2s will cost (1-2)^2+(1-2)^2+(3-2)^2=3 dollars. Note that Evi has to pay (1-2)^2 dollar separately for transforming each of the two 1s.

Sample Input 3

3
4 2 5

Sample Output 3

5

Leaving the 4 as it is and transforming the 2 and the 5 into 4s will achieve the total cost of (2-4)^2+(5-4)^2=5 dollars, which is the minimum.

Sample Input 4

4
-100 -100 -100 -100

Sample Output 4

0

Without transforming anything, Evi's objective is already achieved. Thus, the necessary cost is 0.


use v5.18;
use warnings;
use List::Util;

chomp(my $num = <STDIN>);
say List::Util::sum(1 .. $num);

Score : 100 points

Problem Statement

There are N children in AtCoder Kindergarten. Mr. Evi will arrange the children in a line, then give 1 candy to the first child in the line, 2 candies to the second child, ..., N candies to the N-th child. How many candies will be necessary in total?

Constraints

1≦N≦100

Input

The input is given from Standard Input in the following format:

N

Output

Print the necessary number of candies in total.

Sample Input 1

3

Sample Output 1

6

The answer is 1+2+3=6.

Sample Input 2

10

Sample Output 2

55

The sum of the integers from 1 to 10 is 55.

Sample Input 3

1

Sample Output 3

1

Only one child. The answer is 1 in this case.


use v5.18;
use warnings;

chomp(my $word = <STDIN>);
my @words = split '', $word;
my @stack;

for my $char (@words) {
  if ($char eq 0) {
    push @stack, 0;
  }
  elsif ($char eq 1) {
    push @stack, 1;
  }
  elsif ($char eq 'B') {
    pop @stack;
  }
}

say @stack;

Score : 200 points

Problem Statement

Sig has built his own keyboard. Designed for ultimate simplicity, this keyboard only has 3 keys on it: the 0 key, the 1 key and the backspace key.

To begin with, he is using a plain text editor with this keyboard. This editor always displays one string (possibly empty). Just after the editor is launched, this string is empty. When each key on the keyboard is pressed, the following changes occur to the string:

The 0 key: a letter 0 will be inserted to the right of the string.

The 1 key: a letter 1 will be inserted to the right of the string.

The backspace key: if the string is empty, nothing happens. Otherwise, the rightmost letter of the string is deleted.

Sig has launched the editor, and pressed these keys several times. You are given a string s, which is a record of his keystrokes in order. In this string, the letter 0 stands for the 0 key, the letter 1 stands for the 1 key and the letter B stands for the backspace key. What string is displayed in the editor now?

Constraints

1 ≦ |s| ≦ 10 (|s| denotes the length of s)

s consists of the letters 0, 1 and B.

The correct answer is not an empty string.

Input

The input is given from Standard Input in the following format:

s

Output

Print the string displayed in the editor in the end.

Sample Input 1

01B0

Sample Output 1

00

Each time the key is pressed, the string in the editor will change as follows: 0, 01, 0, 00.

Sample Input 2

0BB1

Sample Output 2

1

Each time the key is pressed, the string in the editor will change as follows: 0, (empty), (empty), 1.


#!perl
use strict;
use warnings;
use utf8;
use feature qw/say/;

my $S = <STDIN>;
do {
    $S =~ s/(0|1)B//;
} while( $S =~ /(0|1)B/ );
$S =~ s/B//;

say $S;


use 5.020;
use utf8;
use strict;
use warnings;
use feature qw/say/;

my $s = <STDIN>;
chomp($s);
my @editor;
for my $ch (split //, $s) {
    push @editor, '0' if $ch eq '0';
    push @editor, '1' if $ch eq '1';
    pop @editor if $ch eq 'B';
}

say(join('', @editor));


#!/usr/bin/env perl
use strict;
use warnings;
use utf8;
use feature qw/say/;

my $S = <STDIN>;
say join(' ', detect($S));

sub detect {
    my ($s) = @_;
    my @c = split(//, $s);
    for my $i (0..scalar(@c)-2) {
        if (($c[$i + 1] || '') eq $c[$i]) {
            return ($i + 1, $i + 2);
        } elsif (($c[$i + 2] || '') eq $c[$i]) {
            return ($i + 1, $i + 3);
        }
    }
    return (-1, -1);
}

Score : 400 points

Problem Statement

Given a string t, we will call it unbalanced if and only if the length of t is at least 2, and more than half of the letters in t are the same. For example, both voodoo and melee are unbalanced, while neither noon nor a is.

You are given a string s consisting of lowercase letters. Determine if there exists a (contiguous) substring of s that is unbalanced. If the answer is positive, show a position where such a substring occurs in s.

Constraints

2 ≦ |s| ≦ 10^5

s consists of lowercase letters.

Partial Score

200 points will be awarded for passing the test set satisfying 2 ≦ N ≦ 100.

Input

The input is given from Standard Input in the following format:

s

Output

If there exists no unbalanced substring of s, print -1 -1.

If there exists an unbalanced substring of s, let one such substring be s_a s_{a+1} ... s_{b} (1 ≦ a < b ≦ |s|), and print a b. If there exists more than one such substring, any of them will be accepted.

Sample Input 1

needed

Sample Output 1

2 5

The string s_2 s_3 s_4 s_5 = eede is unbalanced. There are also other unbalanced substrings. For example, the output 2 6 will also be accepted.

Sample Input 2

atcoder

Sample Output 2

-1 -1

The string atcoder contains no unbalanced substring.


Problem Statement

You are given two integers a and b (a≤b). Determine if the product of the integers a, a+1, …, b is positive, negative or zero.

Constraints

a and b are integers.

-10^9≤a≤b≤10^9

Partial Score

In test cases worth 100 points, -10≤a≤b≤10.

Input

The input is given from Standard Input in the following format:

a b

Output

If the product is positive, print Positive. If it is negative, print Negative. If it is zero, print Zero.

Sample Input 1

1 3

Sample Output 1

Positive

1×2×3=6 is positive.

Sample Input 2

-3 -1

Sample Output 2

Negative

(-3)×(-2)×(-1)=-6 is negative.

Sample Input 3

-1 1

Sample Output 3

Zero

(-1)×0×1=0.


Score : 100 points

Problem Statement

Iroha loves Haiku. Haiku is a short form of Japanese poetry. A Haiku consists of three phrases with 5, 7 and 5 syllables, in this order.

To create a Haiku, Iroha has come up with three different phrases. These phrases have A, B and C syllables, respectively. Determine whether she can construct a Haiku by using each of the phrases once, in some order.

Constraints

1≦A,B,C≦10

Input

The input is given from Standard Input in the following format:

A B C

Output

If it is possible to construct a Haiku by using each of the phrases once, print YES (case-sensitive). Otherwise, print NO.

Sample Input 1

5 5 7

Sample Output 1

YES

Using three phrases of length 5, 5 and 7, it is possible to construct a Haiku.

Sample Input 2

7 7 5

Sample Output 2

NO


#!/usr/bin/env perl
use strict;
use warnings;
use utf8;
use feature qw/say/;

my @ns = @ARGV;
@ns = sort { $a <=> $b } @ns;
if ($ns[0] == 5 && $ns[1] == 5 && $ns[2] == 7) {
    say 'YES';
} else {
    say 'NO';
}


use v5.18; # strict say state
use warnings;
use List::Util qw(reduce first max min sum0);

chomp (my $n = <STDIN>);
chomp (my @l = split / /, <STDIN>);
@l = sort { $a <=> $b } @l;

my $ans = 0;
for my $i (0..(2*$n-1)) {
  $ans += $l[$i] if $i % 2 == 0;
}
say $ans;

Score : 200 points

Problem Statement

Snuke is having a barbeque party.

At the party, he will make N servings of Skewer Meal.

Example of a serving of Skewer Meal

He has a stock of 2N skewers, all of which will be used in Skewer Meal. The length of the i-th skewer is L_i.
Also, he has an infinite supply of ingredients.

To make a serving of Skewer Meal, he picks 2 skewers and threads ingredients onto those skewers.
Let the length of the shorter skewer be x, then the serving can hold the maximum of x ingredients.

What is the maximum total number of ingredients that his N servings of Skewer Meal can hold, if he uses the skewers optimally?

Constraints

1≦N≦100

1≦L_i≦100

For each i, L_i is an integer.

Input

The input is given from Standard Input in the following format:

N
L_1 L_2 ... L_{2N}

Output

Print the maximum total number of ingredients that Snuke's N servings of Skewer Meal can hold.

Sample Input 1

2
1 3 1 2

Sample Output 1

3

If he makes a serving using the first and third skewers, and another using the second and fourth skewers, each serving will hold 1 and 2 ingredients, for the total of 3.

Sample Input 2

5
100 1 2 3 14 15 58 58 58 29

Sample Output 2

135


Score : 500 points

Problem Statement

Snuke is conducting an optical experiment using mirrors and his new invention, the rifle of Mysterious Light.

Three mirrors of length N are set so that they form an equilateral triangle.
Let the vertices of the triangle be a, b and c.

Inside the triangle, the rifle is placed at the point p on segment ab such that ap = X.
(The size of the rifle is negligible.)
Now, the rifle is about to fire a ray of Mysterious Light in the direction of bc.

The ray of Mysterious Light will travel in a straight line, and will be reflected by mirrors, in the same ways as "ordinary" light.
There is one major difference, though: it will be also reflected by its own trajectory as if it is a mirror!
When the ray comes back to the rifle, the ray will be absorbed.

The following image shows the ray's trajectory where N = 5 and X = 2.

It can be shown that the ray eventually comes back to the rifle and is absorbed, regardless of the values of N and X.
Find the total length of the ray's trajectory.

Constraints

2≦N≦10^{12}

1≦X≦N-1

N and X are integers.

Partial Points

300 points will be awarded for passing the test set satisfying N≦1000.

Another 200 points will be awarded for passing the test set without additional constraints.

Input

The input is given from Standard Input in the following format:

N X

Output

Print the total length of the ray's trajectory.

Sample Input 1

5 2

Sample Output 1

12

Refer to the image in the Problem Statement section.
The total length of the trajectory is 2+3+2+2+1+1+1 = 12.