Given 2 numbers A and B, construct a program to print the sum

INPUT:
Each test case consists of a single line containing A and B (0 < A,B < 10^9) separated by a single space.

Input is terminated when A = B = 0

OUTPUT:
For each test case, print a single line

Case <num>: <sum>

Sum < 10^9

Example Input:
1 1
2 3
500 8600
0 0

Example Output:
Case 1: 2
Case 2: 5
Case 3: 9100