RMQ(二维模板)
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//freopen("/Users/zhangzhichao/Documents/HDOJ/HDOJ/1.txt", "r", stdin);#include <stdio.h>#include <iostream>#include <algorithm>#include <cmath>#include <string>#include <vector>#include <string.h>#include <memory>#include <queue>using namespace std;int dp[303][303][9][9];//dp[k][l][i][j]----->从第i行第j列，到第k + (1<<i)行 第l + (1<<j)列 最大的elementint map[303][303];int n, m;void init() { for (int i = 0; i <= (int)log(n*1.0)/log(2.0); ++i) { for (int j = 0; j <= (int)log(m*1.0)/log(2.0); ++j) { if (i + j) for (int k = 1; k <= n - (1<<i) + 1; ++k) { for (int l = 1; l <= m - (1<<j) + 1; ++l) { if (i == 0) { dp[k][l][i][j] = max(dp[k][l][i][j-1], dp[k][l + (1<<(j-1))][i][j-1]);// 因为 dp 范围是 [j, j + 1<<j] 所以二分一下就是这样above } else { dp[k][l][i][j] = max(dp[k][l][i-1][j], dp[k + (1<<(i-1))][l][i-1][j]); } } } } }}int RMQ(int x1, int y1, int x2, int y2) { int k1 = (int)log(n*1.0)/log(2.0); int k2 = (int)log(m*1.0)/log(2.0); x2 = x2 - (1<<k1) + 1; y2 = y2 - (1<<k2) + 1; return max(max(dp[x1][y1][k1][k2], dp[x1][y2][k1][k2]), max(dp[x2][y1][k1][k2], dp[x2][y2][k1][k2]));}
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