(devskills)POS System.cPP

/*                                       CODEMAN
                                        Arif Khan Nihar
                                   Problem - POS System

                                   */

#include<bits/stdc++.h>

using namespace std;

int main()
{
    double p1,amount;
    int q1,ans,n,k,g_a;
    cin >> n;
    for(int i = 1 ; i <= n ; i++) {
            amount = 0;
            cin >> k;
    while( k-- ) {
        cin >> p1 >> q1;
        amount  +=  (p1*q1);
        }
    cin  >>  g_a;
    cout << "Case " << i << ": " << (int)(g_a - amount) << endl ;
    }
    return 0;
}