#include<iostream>
using namespace std;

int main()
{
    int T;
    while( cin >> T )
    {
        for( int i = 1 ; i <= T ; i++ )
        {
            int a, b;
            cin >> a >> b;

            int sum = 0;
            for( int j = a ; j <= b ; j++ )
                if( j % 2 )
                    sum += j;
            cout << "Case " << i << ": " << sum << endl;
        }
    }
    return 0;
}