1030

#include<bits/stdc++.h>
using namespace std;

int main()
{
    int x,y,i,store,j;
    int n;
    cin>>n;
    for(int k=1; k<=n; k++)
    {
        cin>>x>>y;
        int a[x];
        fill( a, a+x, 0 );

        int count1=0;
        store=0;
        while(1)
        {
            for(j=0; j<x; j++)
            {
                count1++;

                if(a[j]==1)
                {
                    count1--;

                    continue;
                }
                if(count1==y)
                {
                    store=j;
                }
                if(count1==y+1)
                {
                    a[j]=1;
                    count1=1;
                }
            }

            int mycount = count (a, a+x, 1);
            if(mycount==x-1)
            {
                break;
            }

        }
        if(store==0)
        {
            cout<<"Case "<<k<<": "<<x<<endl;
        }
        else

        cout<<"Case "<<k<<": "<<store<<endl;

    }
    return 0;

}