Submission #926635

#	Time	Username	Problem	Language	Result	Execution time	Memory
926635		myst6	Secret (JOI14_secret)	C++17	100 / 100	366 ms	4612 KiB

secret

#pragma GCC optimize("O3,unroll-loops")
#pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt")

#include "secret.h"

const int maxn = 1000;
int table[10][maxn];
int mask[maxn];
int base[maxn];
int B = 0;

void fill(int L, int R) {
  if (L == R) return;
  int M = (L + R) / 2;
  table[B][M] = base[M];
  table[B][M+1] = base[M+1];
  for (int i=M-1; i>=L; i--) table[B][i] = Secret(base[i], table[B][i+1]);
  for (int i=M+2; i<=R; i++) table[B][i] = Secret(table[B][i-1], base[i]);
  for (int i=M+1; i<=R; i++) mask[i] ^= 1 << B;
  ++B; fill(L, M); fill(M+1, R); --B;
}

void Init(int N, int A[]) {
  for (int i=0; i<N; i++) base[i] = A[i];
  fill(0, N-1);
}

int Query(int L, int R) {
  if (L == R) return base[L];
  int B = __builtin_ctz(mask[L] ^ mask[R]);
  return Secret(table[B][L], table[B][R]);
}

• Subtask 1: 100 / 100