I have a set of positive integers S. Can you find two non-empty, distinct subsets with the same sum?
Note: A subset is a set that contains only elements from S, and two subsets are distinct if they do not have exactly the same elements.
The first line of the input gives the number of test cases, T. T test cases follow, one per line. Each test case begins with N, the number of positive integers in S. It is followed by N distinct positive integers, all on the same line.
For each test case, first output one line containing "Case #x:", where x is the case number (starting from 1).
No two numbers in S will be equal.
1 ≤ T ≤ 10.
N is exactly equal to 20.
Each number in S will be a positive integer less than 105.
N is exactly equal to 500.
Each number in S will be a positive integer less than 1012.