#include <bits/stdc++.h>
using namespace std;
int a[10][10];
int main() {
  int n;
  scanf("%d", &n);
  for (int i = 0; i < n; ++i) {
    for (int j = 0; j < n; ++j) {
      scanf("%d", &a[i][j]);
    }
  }
  for (int k = 0; k < n; ++k) {
    for (int i = 0; i < n; ++i) {
      for (int j = 0; j < n; ++j) {
        a[i][j] = min(a[i][j], a[i][k] + a[k][j]);
      }
    }
  }
  int ans = 0;
  for (int i = 0; i < n; ++i) {
    for (int j = 0; j < n; ++j) {
      ans = max(ans, a[i][j]);
    }
  }
  printf("%d\n", ans);
  return 0;
}
