1. 

/**
* FWP, Ausgewählte Probleme aus dem ACM Programming Contest, SS10
* Problem: 541 Error Correction
*
* @author Robert Reichart
*
* Status : Accepted
* Runtime: 0.552
*/

import java.util.*;
class Main{
public static void main(String... args){
Scanner in = new Scanner(System.in);
while (in.hasNextInt())
{
int size = in.nextInt();
if (size>0){
int[][] values = new int[size+1][size+1];

//Daten in Array einlesen
for (int i=0;i<size;i++){
for (int k=0;k<size;k++){
values[k][i] = in.nextInt();
}
}

int[] rowsum = new int[size];
int[] colsum = new int[size];
ArrayList<Integer> oddrow = new ArrayList<Integer>();
ArrayList<Integer> oddcol = new ArrayList<Integer>();

for (int i=0;i<size;i++){
int tmp=0;
for (int k=0;k<size;k++){
tmp+=values[k][i];
}
rowsum[i]=tmp;
if (tmp%2==1){oddrow.add(i+1);}
}
for (int i=0;i<size;i++){
int tmp=0;
for (int k=0;k<size;k++){
tmp+=values[i][k];
}
colsum[i]=tmp;
if (tmp%2==1){oddcol.add(i+1);}
}

if (oddrow.size() == 0 && oddcol.size() == 0) {
System.out.print("OK\n");
}
else if (oddrow.size() == 1 && oddcol.size() == 1) {
System.out.print("Change bit (" + oddrow.get(0) + "," + oddcol.get(0) + ")\n");
}
else {
System.out.print("Corrupt\n");
}

}
}
}
}