#include <fstream.h>

ifstream in("error.in");

int n, i, j;
int m[100][100];
int sumr[100], sumd[100];

main()
{
  while(1)
    {
      in >> n;
      if (n == 0) return 0;
      for (i = 0; i < n; i++)
	sumd[i] = 0;
      for (i = 0; i < n; i++)
	{
	  sumr[i] = 0;
	  for (j = 0; j < n; j++)
	    {
	      in >> m[i][j];
	      sumr[i] = (sumr[i] + m[i][j]) & 1;
	      sumd[j] = (sumd[j] + m[i][j]) & 1;
	    }
	}
      int rnok = -1;
      int dnok = -1;
      for (i = 0; i < n; i++)
	{
	  if (sumr[i] != 0)
	    {
	      if (rnok != -1)
		{
		  cout << "Corrupt";
		  goto next;
		}
	      else
		rnok = i;
	    }
	  if (sumd[i] != 0)
	    {
	      if (dnok != -1)
		{
		  cout << "Corrupt";
		  goto next;
		}
	      else
		dnok = i;
	    }
	}
      if (rnok == -1 && dnok == -1)
	cout << "OK";
      else
	cout << "Change bit (" << rnok + 1 << "," << dnok  + 1 << ")";
    next:
      cout << endl;
    }
  return 0;
}