# Brave boy

Time Limit: 1000 ms

Memory Limit: 65535 ms

## Description

Snow is a brave boy.He always has some new ideas.Now he wanna redefine the "+" operator for strings such that "a"+"a"="a", "b"+"b"="c",...,"b"+"z"="ba".Now you have to add two strings a and b using the operator "+".Notice that the strings consist of only lower-case characters.

## Input

The first line contains an integer t ( 1 <= t <= 100 ): the number of test cases. Then for each test case:Each case contains two strings.

## Output

For each test case, output the result in the form of sample.You should print the case number and the sum of the two strings.

## Sample Input

2
aa
a
abc
cba


## Sample Output

Case 1: aa
Case 2: ccc


None