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bff4ec7 | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 | /*@ Import Lean
import Algorithms.discretize.lean.helper_lib
open scoped SimpleC
*/
/*@ Extern Coq (permutation : list Z -> list Z -> Prop) */
/*@ Extern Coq (increasing : list Z -> Prop) */
/*@ Extern Coq (same_outside_range : list Z -> list Z -> Z -> Z -> Prop) */
/*@ Extern Coq (partitioned_at : list Z -> Z -> Z -> Z -> Prop) */
/*@ Extern Coq (sorted_range : list Z -> Z -> Z -> Prop) */
/*@ Extern Coq (partition_scan_inv : list Z -> list Z -> Z -> Z -> Z -> Z -> Z -> Prop) */
/*@ Extern Coq (strict_increasing : list Z -> Prop) */
/*@ Extern Coq (dedup_scan_inv : list Z -> list Z -> list Z -> Z -> Z -> Prop) */
/*@ Extern Coq (discretize_result : list Z -> Z -> list Z -> Z -> Prop) */
/*@ Extern Coq (query_forward_result : list Z -> Z -> Z -> Z -> Prop) */
/*@ Extern Coq (query_forward_search_inv : list Z -> Z -> Z -> Z -> Z -> Prop) */
void swap(int *arr, int i, int j)
/*@ With n l
Require 0 <= i && i < n && 0 <= j && j < n &&
IntArray::full(arr, n, l)
Ensure IntArray::full(arr, n,
replace_Znth(j, Znth(i, l, 0), replace_Znth(i, Znth(j, l, 0), l)))
*/
{
int tmp = arr[i];
arr[i] = arr[j];
arr[j] = tmp;
}
int partition(int *arr, int n, int low, int high)
/*@ With l
Require 0 <= low && low <= high && high < n &&
IntArray::full(arr, n, l)
Ensure low <= __return && __return <= high &&
exists l1,
permutation(l, l1) &&
same_outside_range(l, l1, low, high) &&
partitioned_at(l1, low, high, __return) &&
IntArray::full(arr, n, l1)
*/
{
int pivot = arr[high];
int i = low - 1;
/*@ Inv Assert
exists l1,
arr == arr@pre && n == n@pre &&
low == low@pre && high == high@pre &&
pivot == Znth(high, l, 0) &&
0 <= low && low <= high && high < n &&
low - 1 <= i && i < j && j <= high &&
partition_scan_inv(l, l1, low, high, pivot, i, j) &&
IntArray::full(arr, n, l1)
*/
for (int j = low; j < high; j++) {
if (arr[j] <= pivot) {
i++;
swap(arr, i, j);
}
}
swap(arr, i + 1, high);
return i + 1;
}
void quicksort_range(int *arr, int n, int left, int right)
/*@ With l
Require 0 <= n && 0 <= left && -1 <= right && right < n &&
IntArray::full(arr, n, l)
Ensure exists l1,
permutation(l, l1) &&
same_outside_range(l, l1, left, right) &&
sorted_range(l1, left, right) &&
IntArray::full(arr, n, l1)
*/
{
if (left < right) {
int p = partition(arr, n, left, right);
if (p > left) {
quicksort_range(arr, n, left, p - 1);
}
if (p < right) {
quicksort_range(arr, n, p + 1, right);
}
}
}
void int_array_quicksort(int *arr, int n)
/*@ With l
Require 1 <= n && n <= 50000 &&
IntArray::full(arr, n, l)
Ensure exists l1,
permutation(l, l1) &&
increasing(l1) &&
IntArray::full(arr, n, l1)
*/
{
quicksort_range(arr, n, 0, n - 1);
}
int discretize(const int *src, int n, int *dest_map)
/*@ With src_l
Require Zlength(src_l) == n &&
1 <= n && n <= 50000 &&
IntArray::full(src, n, src_l) *
IntArray::undef_full(dest_map, n)
Ensure exists out_l,
discretize_result(src_l, n, out_l, __return) &&
IntArray::full(src, n, src_l) *
IntArray::full(dest_map, n, out_l)
*/
{
/*@ Inv Assert
Zlength(src_l) == n@pre &&
1 <= n@pre && n@pre <= 50000 &&
0 <= i && i <= n@pre &&
src == src@pre && dest_map == dest_map@pre && n == n@pre &&
IntArray::full(src@pre, n@pre, src_l) *
IntArray::full(dest_map@pre, i, sublist(0, i, src_l)) *
IntArray::undef_seg(dest_map@pre, i, n@pre)
*/
for (int i = 0; i < n; i++) {
dest_map[i] = src[i];
}
/*@ Assert
Zlength(src_l) == n@pre &&
1 <= n@pre && n@pre <= 50000 &&
src == src@pre && dest_map == dest_map@pre && n == n@pre &&
IntArray::full(src@pre, n@pre, src_l) *
IntArray::full(dest_map@pre, n@pre, src_l)
*/
int_array_quicksort(dest_map, n);
int slow = 0;
/*@ Inv Assert
exists sorted_l cur_l,
Zlength(src_l) == n@pre &&
1 <= n@pre && n@pre <= 50000 &&
src == src@pre && dest_map == dest_map@pre && n == n@pre &&
0 <= slow && slow < fast && 1 <= fast && fast <= n@pre &&
dedup_scan_inv(src_l, sorted_l, cur_l, slow, fast) &&
IntArray::full(src@pre, n@pre, src_l) *
IntArray::full(dest_map@pre, n@pre, cur_l)
*/
for (int fast = 1; fast < n; fast++) {
if (dest_map[fast] != dest_map[slow]) {
slow++;
dest_map[slow] = dest_map[fast];
}
}
/*@ Assert
exists out_l,
Zlength(src_l) == n@pre &&
1 <= n@pre && n@pre <= 50000 &&
src == src@pre && dest_map == dest_map@pre && n == n@pre &&
discretize_result(src_l, n@pre, out_l, slow + 1) &&
IntArray::full(src@pre, n@pre, src_l) *
IntArray::full(dest_map@pre, n@pre, out_l)
*/
return slow + 1;
}
int query_forward(const int *map, int map_size, int target)
/*@ With map_l
Require Zlength(map_l) == map_size &&
0 <= map_size && map_size <= 50000 &&
strict_increasing(map_l) &&
IntArray::full(map, map_size, map_l)
Ensure query_forward_result(map_l, map_size, target, __return) &&
IntArray::full(map, map_size, map_l)
*/
{
int low = 0;
int high = map_size - 1;
/*@ Inv Assert
Zlength(map_l) == map_size@pre &&
0 <= map_size@pre && map_size@pre <= 50000 &&
strict_increasing(map_l) &&
map == map@pre && map_size == map_size@pre && target == target@pre &&
0 <= low && low <= high + 1 && high < map_size@pre &&
query_forward_search_inv(map_l, map_size@pre, target@pre, low, high) &&
IntArray::full(map@pre, map_size@pre, map_l)
*/
while (low <= high) {
int mid = low + (high - low) / 2;
/*@ Assert
Zlength(map_l) == map_size@pre &&
0 <= map_size@pre && map_size@pre <= 50000 &&
strict_increasing(map_l) &&
map == map@pre && map_size == map_size@pre && target == target@pre &&
0 <= low && low <= mid && mid <= high && high < map_size@pre &&
query_forward_search_inv(map_l, map_size@pre, target@pre, low, high) &&
IntArray::full(map@pre, map_size@pre, map_l)
*/
if (map[mid] == target) {
return mid;
} else if (map[mid] < target) {
low = mid + 1;
} else {
high = mid - 1;
}
}
/*@ Assert
Zlength(map_l) == map_size@pre &&
0 <= map_size@pre && map_size@pre <= 50000 &&
strict_increasing(map_l) &&
map == map@pre && map_size == map_size@pre && target == target@pre &&
0 <= low && low <= high + 1 && high < map_size@pre &&
query_forward_search_inv(map_l, map_size@pre, target@pre, low, high) &&
query_forward_result(map_l, map_size@pre, target@pre, -1) &&
IntArray::full(map@pre, map_size@pre, map_l)
*/
return -1;
}
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