836 - Largest Submatrix, uva

#include<iostream>
#include<cstdio>
#include<cstring>
#define db(a) cout << #a << " = " << a << endl
#define db2(a, b) cout << #a << " = " << a << " " << #b << " = " << b << endl
#define db3(a, b, c) cout << #a << " = " << a << " " << #b << " = " << b << " " << #c << " = " << c << endl
using namespace std;
int main() {
 #ifdef dennisbot
  freopen("in.in", "r", stdin);
  freopen("ou.out", "w", stdout);
 #endif
 int test, i, j, n, matriz[100][100], fila[100], div = 1, sum = 0, max = 0;
 char var[100];
 scanf("%d\n", &test);
 while (test--) {
  i = 0;
  while (gets(var) && var[0] != '\0') {
   n = strlen(var);
   for (int j = 0; j < n; j++) {
    matriz[i][j] = var[j] - 48;
   }
   i++;
  }
  max = 0;
  for (int i = 0; i < n; i++) {
   memset(fila, 0, sizeof fila);
   for (int ii = i; ii < n; ii++) {
    sum = 0;
    for (int j = 0; j < n; j++) {
     fila[j] += matriz[ii][j];
     if (fila[j] == ii - i + 1) sum += fila[j];
     else sum = 0;
     if (sum > max) max = sum;
    }
   }
  }
  printf("%d\n", max);
  if (test != 0) puts("");
 }
 return 0;
}