#include <bits/stdc++.h>
using namespace std;
int main() 
{
	int t;
	cin>>t;
	for(int x=0;x<t;x++)
	{
	    int n;
	    int upleftCount=0;
	    int uprightCount=0;
	    int lowleftCount=0;
	    int lowrightCount=0;
	    cin>>n;
	    for(int i=0;i<2*n;i++)
	    {
	        for(int j=0;j<2*n;j++)
	        {
	            char val;
	            cin>>val;
	            if(val=='I')
	            {
	                if(i<=n/2)
	                {
	                    if(j<=n/2)
	                        upleftCount++;
	                    else
	                        uprightCount++;
	                }
	                else
	                {
	                    if(j<=n/2)
	                        lowleftCount++;
	                    else
	                        lowrightCount++;
	                }
	            }
	        }
	    }
	    int count=0;
        if((upleftCount+uprightCount)!=(lowleftCount+lowrightCount))
            count+=abs(upleftCount+uprightCount-lowleftCount-lowrightCount);
        else if((upleftCount+lowleftCount)!=(uprightCount+lowrightCount))
            count+=abs(upleftCount+lowleftCount-uprightCount-lowrightCount);
	    cout<<"Case #"<<x+1<<": "<<count<<endl;
	}
	return 0;
}