第3次了 关于最大01矩阵的
这次找 尽可能大 不相互包含的
寻找策略是 下一层1的长度 不等于我当前这层长度
剩下的依然是 单调栈维护1矩阵 左右到哪里
#include<bits/stdc++.h>
using namespace std;
const int maxn = 3000 + 10;
int n, m;
int a[maxn][maxn], dp[maxn][maxn];
int vis[maxn][maxn];
int l[maxn], r[maxn], sum[maxn][maxn];
int que[maxn], head;
signed main() {
scanf("%d %d", &n, &m);
for(int i = 1; i <= n; i++){
for(int j = 1; j <= m; j ++) {
scanf("%1d", &a[i][j]);
sum[i][j] = sum[i][j - 1] + a[i][j];
if(a[i][j] == 1) dp[i][j] = dp[i - 1][j] + 1;
else dp[i][j] = 0;
}
}
int ans = 0;
for(int i = 1; i <= n; i ++) {
head = 0; que[++head] = 0;
for(int j = 1; j <= m; j ++) {
while(head > 0 && dp[i][j] <= dp[i][que[head]]) head--;
l[j] = que[head] + 1;
que[++head] = j;
}
head = 0; que[++head] = m + 1;
for(int j = m; j >= 1; j --) {
while(head > 0 && dp[i][j] <= dp[i][que[head]]) head--;
r[j] = que[head] - 1;
que[++head] = j;
}
for(int j = 1; j <= m; j ++) {
if(dp[i][j] == 0) continue;
if(sum[i][r[j]] - sum[i][l[j] - 1] != r[j] - l[j] + 1) continue;
if(vis[l[j]][r[j]] == i) continue; //标记K层
if(sum[i + 1][r[j]] - sum[i + 1][l[j] - 1] == r[j] - l[j] + 1) continue;
ans ++;
vis[l[j]][r[j]] = i;
}
}
printf("%d\n", ans);
return 0;
}