func_code_string: #include <bits/stdc++.h>   using namespace std;   void MAIN();   int main() {     MAIN();     return 0;   }   const long long N = 5e3 + 1, mod = 1e9 + 7;   int n, m, best[N][N], len[N][N];   char s[N][N];   void MAIN() {     scanf( %d%d , &n, &m);     for (int i = 1; i <= n; ++i) {       scanf( %s , s[i] + 1);       for (int j = 1; j <= m; ++j) {         if (s[i][j] ==  1 ) {           len[i][j] = len[i][j - 1] + 1;         }         ++best[j][len[i][j]];       }     }     for (int i = m - 1; i >= 1; --i) {       for (int j = 1; j <= m; ++j) {         best[j][i] += best[j][i + 1];       }     }     int ans = 0;     for (int i = 1; i <= m; ++i) {       for (int len = 1; len <= m; ++len) {         ans = max(ans, len * best[i][len]);       }     }     printf( %d , ans);   }   