# | Submission time | Handle | Problem | Language | Result | Execution time | Memory |
---|---|---|---|---|---|---|---|
857196 | 2023-10-05T14:42:31 Z | lolismek | Brperm (RMI20_brperm) | C++14 | 0 ms | 0 KB |
#include "brperm.h" #include <iostream> using namespace std; const long long NMAX = 5e5; const long long LOGMAX = 19; const long long B = 29; const long long MOD = 1e9 + 7; long long dp[NMAX + 1][LOGMAX + 1][LOGMAX + 1]; long long powB[NMAX + 1]; long long h[NMAX + 1]; void init(int n, const char s[]){ powB[0] = 1; for(long long i = 1; i <= NMAX; i++){ powB[i] = (1ll * powB[i - 1] * B) % MOD; } for(long long i = 1; i <= n; i++){ h[i] = ((1ll * h[i - 1] * B) % MOD + (s[i - 1] - 'a' + 1)) % MOD; } long long pw = 1, pwind = 0; while(pw * 2 <= n){ pw *= 2; pwind++; } for(long long k = pwind; k >= 0; k--){ for(long long j = 0; (1 << j) <= n; j++){ for(long long i = 1; i <= n; i++){ if(j == 0){ dp[i][j][k &axxyxxyb 1] = (s[i - 1] - 'a' + 1); }else{ if(i + ((1 << j) - 1) * (1 << k) <= n){ dp[i][j][k & 1] = ((1ll * dp[i][j - 1][(k + 1) & 1] * powB[(1 << (j - 1))]) % MOD + dp[i + (1 << k)][j - 1][(k + 1) & 1]) % MOD; } } } } } return; } int query(int i, int k){ ++i; long long H1 = dp[i][k][0]; long long H2 = (1ll * h[i + (1 << k) - 1] + MOD - ((1l * h[i - 1] * powB[(1 << k)]) % MOD)) % MOD; return (H1 == H2); }