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4.77 kB
| // Tree Training | |
| // Solution by Jacob Plachta | |
| using namespace std; | |
| template<typename T> T Abs(T x) { return(x < 0 ? -x : x); } | |
| template<typename T> T Sqr(T x) { return(x * x); } | |
| string plural(string s) { return(Sz(s) && s[Sz(s) - 1] == 'x' ? s + "en" : s + "s"); } | |
| const int INF = (int)1e9; | |
| const LD EPS = 1e-12; | |
| const LD PI = acos(-1.0); | |
| bool Read(int& x) { | |
| char c, r = 0, n = 0; | |
| x = 0; | |
| for (;;) { | |
| c = GETCHAR(); | |
| if ((c < 0) && (!r)) | |
| return(0); | |
| if ((c == '-') && (!r)) | |
| n = 1; | |
| else if ((c >= '0') && (c <= '9')) | |
| x = x * 10 + c - '0', r = 1; | |
| else if (r) | |
| break; | |
| } | |
| if (n) | |
| x = -x; | |
| return(1); | |
| } | |
| int N, M; | |
| char S[LIM]; | |
| int Z[LIM]; | |
| int DS[LIM]; | |
| int TreeCnt(int h) // # of nodes in binary tree with height h | |
| { | |
| return((1 << (h + 1)) - 1); | |
| } | |
| // E(z, s, h) = max. *s which can fit alongside z 0s (with s *s before the 1st 0) in a tree of height at most h (only relevant for z > 0) | |
| int E(int z, int s, int h) | |
| { | |
| if (h >= LOG) | |
| return(N); | |
| int left = min(s, h + 1 - z); // *s at root and along leftmost branch | |
| int cnt = TreeCnt(h); // full tree | |
| cnt -= TreeCnt(h - left); // subtract subtree of 1st 0 | |
| if (cnt >= s) | |
| cnt += TreeCnt(h - left - 1); // add back right subtree of 1st 0 | |
| return(cnt); | |
| } | |
| // F(p, z, s) = min. tree height for p *s, z 0s, and s *s before 1st 0 (s ignored if z = 0) | |
| int F(int p, int z, int s) | |
| { | |
| int r1 = z ? (s > 0 ? z : z - 1) : 0; | |
| int r2 = max(r1, min(LOG, p + z - 1)); | |
| while (r1 < r2) | |
| { | |
| int m = (r1 + r2) >> 1; | |
| if ((z ? E(z, s, m) : TreeCnt(m)) >= p) | |
| r2 = m; | |
| else | |
| r1 = m + 1; | |
| } | |
| return(r1); | |
| } | |
| int ProcessCase() | |
| { | |
| int i, j, z; | |
| // input | |
| scanf("%s", &S); | |
| N = strlen(S); | |
| // find 0s | |
| M = 0; | |
| Z[M++] = -1; | |
| Fox(i, N) | |
| if (S[i] == '0') | |
| Z[M++] = i; | |
| Z[M++] = N; | |
| // A) z = 0 | |
| int ans = 0; | |
| int v = 0, s = 0; | |
| Fill(DS, 0); | |
| Fox1(i, M - 1) | |
| { | |
| int x = Z[i] - Z[i - 1] - 1; // sequence of x *s before ith 0 | |
| v += x; | |
| DS[2]--, DS[x + 2]++; | |
| } | |
| Fox1(i, N) | |
| { | |
| s += DS[i]; | |
| v += s; | |
| ans = (ans + (LL)v * F(i, 0, 0)) % MOD; | |
| } | |
| // B) 1 <= z <= LOG | |
| Fox1(z, LOG) // z 0s | |
| { | |
| Fox1(i, M - z - 1) // ith 0 as the leftmost 0 | |
| { | |
| int j = i + z - 1; | |
| int c1 = Z[i] - Z[i - 1] - 1; // c1 *s to the left | |
| int c2 = Z[j + 1] - Z[j] - 1; // c2 *s to the right | |
| int m = Z[j] - Z[i] + 1 - z; // m *s in between | |
| Fox(s, c1 + 1) // use s *s to the left | |
| { | |
| int p = s + m, mp = s + m + c2; | |
| int h = F(p, z, s); | |
| while (p <= mp) | |
| { | |
| int p2 = min(mp, E(z, s, h)); | |
| ans = (ans + (LL)(p2 - p + 1) * h) % MOD; | |
| p = p2 + 1, h++; | |
| } | |
| } | |
| } | |
| } | |
| // C) z > LOG | |
| Fox1(i, M - 2) // count contribution of the ith 0 | |
| { | |
| // add # of intervals containing it | |
| ans = (ans + (LL)(Z[i] + 1) * (N - Z[i])) % MOD; | |
| // subtract # of intervals containing it, with <= LOG 0s | |
| FoxI(j, max(1, i - LOG + 1), i) // jth 0 as the leftmost 0 | |
| { | |
| int k = min(M - 1, j + LOG); // first disallowed 0 | |
| int c = (LL)(Z[j] - Z[j - 1]) * (Z[k] - Z[i]) % MOD; | |
| ans = (ans + MOD - c) % MOD; | |
| } | |
| // subtract # of intervals starting with it, with > LOG 0s | |
| int j = i + LOG; | |
| if (j < M) | |
| ans = (ans + MOD - (N - Z[j])) % MOD; | |
| } | |
| return(ans); | |
| } | |
| int main() | |
| { | |
| int T, t; | |
| Read(T); | |
| Fox1(t, T) | |
| printf("Case #%d: %d\n", t, ProcessCase()); | |
| return(0); | |
| } |