UVa 11464

#include <cstdio>
#include <iostream>
using namespace std;


const int INF = 0x7fffffff>>2;
int a[20][20];
int b[20][20];
int ans;
int n;


inline void make()
{
int num=0;
for(int i=2;i<=n;i++)
for(int j=1;j<=n;j++)
{
int sum = 0;
if(i>2) sum+=b[i-2][j];
if(j>1) sum+=b[i-1][j-1];
if(j<n) sum+=b[i-1][j+1];
b[i][j] = sum % 2;
if(b[i][j] == 0 && a[i][j] == 1) return;
}
for(int i=1;i<=n;i++)
for(int j=1;j<=n;j++)
{
if(b[i][j]==0 && a[i][j] ==1) return;
if(a[i][j] != b[i][j])
num++;
}
ans = min(ans,num);
return ;
}
inline void search(int k)
{
if(k>n)
{
make();
return ;
}


b[1][k]=0;
search(k+1);

b[1][k]=1;
search(k+1);

b[1][k]=0;
}


int main()
{
int T=0;
scanf("%d",&T);
for(int t=1;t<=T;t++)
{
ans = INF;
scanf("%d",&n);
for(int i=1;i<=n;i++)
for(int j=1;j<=n;j++)
{
scanf("%d",&a[i][j]);
}
search(1);
if(ans == INF) ans=-1;
printf("Case %d: %d\n",t,ans);
}
return 0;
}