UVA - 10925 - Krakovia

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.math.BigInteger;

public class Main {

    public static void main(String[] args) throws IOException {

        InputStreamReader isr = new InputStreamReader(System.in);
        BufferedReader br = new BufferedReader(isr);
        StringBuffer sb = new StringBuffer("");
        int cases=0;
        while (true){
            cases++;
            String[] str = br.readLine().split(" ");
            int n=Integer.parseInt(str[0]);
            int fr=Integer.parseInt(str[1]);
            if(n==0 && fr==0)
                break;
            BigInteger sum=BigInteger.ZERO;
            for(int i=0;i<n;i++){
                sum=sum.add(new BigInteger(br.readLine()));
            }
            sb.append("Bill #").append(cases).append(" costs ").append(sum).append(": each friend should pay ").append(sum.divide(BigInteger.valueOf(fr))).append("\n\n");
        }
        System.out.print(sb);
    }
}