View Code of Problem 3689

import java.util.Scanner;
import java.math.BigInteger;

public class Main
{
  public static void main(String[] args)
  {
    Scanner input=new Scanner(System.in);
    int t=input.nextInt();
    for(int i=1;i<=t;i++)
    {
      BigInteger a =input.nextBigInteger();
      BigInteger b= input.nextBigInteger();
      System.out.println("Case #"+i+":");
      System.out.println(a.subtract(b));
    }
  }
}