func_code_string: #include <bits/stdc++.h>   using namespace std;   const int inf = 0x3f3f3f3f;   const long long infLL = 0x3f3f3f3f3f3f3f3fLL;   const int hash_mod = 1000037;   const double eps = 1e-10;   const double pi = acos(-1);   const int maxn = 5000 + 5;   int n, m;   char s[maxn];   int f[maxn][maxn], g[maxn];   int main() {     scanf( %d%d , &n, &m);     for (int i = 0; i < n; ++i) {       scanf( %s , s + 1);       for (int j = 1; j <= m; ++j)         if (s[j] ==  1 ) f[i][j] = f[i][j - 1] + 1;     }     int res = 0;     for (int j = 1; j <= m; ++j) {       memset(g, 0, sizeof(g));       for (int i = 0; i < n; ++i) g[f[i][j]]++;       int t = 0;       for (int i = j; i > 0; --i) {         t += g[i];         res = max(res, i * t);       }     }     printf( %d n , res);     return 0;   }   