#include <bits/stdc++.h>   using namespace std;   int n, d, sum, ans;   char s[105];   int main() {     scanf( %d %d , &n, &d);     for (int i = 0; i < d; i++) {       scanf( %s , s);       bool ok = true;       for (int j = 0; j < n; j++)         if (s[j] ==  0 ) ok = false;       if (ok)         sum = 0;       else         sum++, ans = max(ans, sum);     }     printf( %d n , ans);     return 0;   }   