I'll play a trick on you 代码的书写

Problem Description
Please look the picture carefully. Then I'll give you two integers and your task is output the third one.
Please never doubt the picture.

Input
The first line is a number T(1<=T<=30), represents the number of case. The next T blocks follow each indicates a case.
Each case contains two integers A,B (1<=B<=A<=10100)

Output
For each case, output the number of case and the third integer.(as shown in the sample output)

Sample Input
3
99 72
45 27
39 18

Sample Output
Case 1: 27
Case 2: 18
Case 3: 21