HUST 2016招新选拔

From: 2016-03-06 14:00:00 To: 2016-03-06 17:30:00 Now: 2017-09-24 21:47:09 Status: Public

F - A Special Property

Time Limit: 1s Memory Limit: 512MB

Submissions: 63 Solved: 28
Description

Given a boolean matrix, which means every element of it is either 0 or 1. If each row and each column of it has an even sum, we call it a magic matrix.

For example:

1 0 1 0

0 0 0 0

1 1 1 1

0 1 0 1

is a magic matrix.

If one magic is not a matrix, we want to know whether we can change only one bit to transform it into a magic matrix, or it should be treated as corrupt.

Input

The input file will contain more than one test cases.

The first line of each test case contains one integer n(n<100), which represents the size of the matrix.

The following n lines represents a boolean matrix.

Output

For each input, print one line.

Print "OK" if the given matrix is a magic matrix.

Print "Chang bit (i,j)" if change bit (i, j) can make it a magic matrix.

Print "Corrupt" if the given matrix is not OK and cannot be transform into a magic matrix with one bit changed.

Sample Input
4
1 0 1 0
0 0 0 0
1 1 1 1
0 1 0 1
4
1 0 1 0
0 1 1 0
1 1 1 1
0 1 0 1
4
1 0 1 0
0 0 1 0
1 1 1 1
0 1 0 1
0
Sample Output
OK
Corrupt
Change bit (2,3)
Hint
Source