hdu 2830 Matrix Swapping II

题目：http://acm.hdu.edu.cn/showproblem.php?pid=2830

又是和1505一个类型的。。。

下面是AC代码：

#include <iostream>using namespace std;const int N = 1002;char a;  int h[N], hash[N];int n, m;int main(){int max;while (scanf("%d %d", &n, &m) != EOF){int i, j;for (j=0; j<m; j++)h[j] = 0;max = 0;for (i=0; i<n; i++){getchar();for (j=0; j<N; j++)hash[j] = 0;    for (j=0; j<m; j++){scanf("%c", &a);if (a == '1')h[j] += 1;elseh[j] = 0;hash[h[j]]++;}int tf=0;for (j=N-2; j>=0; j--){hash[j] += hash[j+1];tf = j*hash[j];if (max < tf)max = tf;}}printf("%d\n", max);}return 0;}