/*
TASK:oldmap
LANG:C++
*/

#include <iostream>
using namespace std;

int N;
long a[501][501];

int main() {
  int i,j,k;
  cin >> N;
  for (i = 1; i <= N; i++)
    for (j = 1; j <= N; j++)
      cin >> a[i][j];
  for (k = 1; k <= N; k++)
    for (i = 1; i <= N; i++)
      for (j = 1; j <= N; j++)
        if (a[i][k] + a[k][j] == a[i][j]&&k!=i&&k!=j&&i!=j)
          { a[i][j] = 0; a[j][i] = 0; }
  for (i = 1; i <= N; i++)
    for (j = i+1; j <= N; j++)
      if (a[i][j] > 0) cout << i << " " << j << " " << a[i][j] << endl;
}
