The Pilots Brothers' refrigerator

http://poj.org/problem?id=2965

#include<stdio.h>
#include<string.h>
int arr[4][4];//存储状态
int main()
{
    int i,j;
    char ch;
    memset(arr[0],0,sizeof(arr[0]));
    for (i = 0; i < 4; i ++)
    {
        for (j = 0; j < 4; j ++)
        {
            ch = getchar();
            if(ch=='+')
            {
                arr[i][j] = !arr[i][j];
                for (int k = 0; k < 4; k ++)
                {
                    arr[i][k] = !arr[i][k];
                    arr[k][j] = !arr[k][j];
                }
            }
        }
        getchar();
    }
    int ans = 0;
    for (i = 0; i < 4; i ++)
    {
        for (j = 0 ; j < 4; j ++)
        {
            if(arr[i][j])//状态为1的为需要转换的位置
                ans++;
        }
    }
    printf("%d
",ans);
    for (i = 0; i < 4; i ++)
    {
        for (j = 0; j < 4; j ++)
        {
            if(arr[i][j])
                printf("%d %d
",i+1,j+1);
        }
    }
    return 0;
}