Problem Statement:
Given a set of N integer A = {1, 2, 3, ... , N} and an integer S, your task is to find a way to insert an operator '+' or '-' to every neighbor pair of A, that the result of the expression after insert equal to S.


Input Format:
The first contains T denoting the number of test cases ( 0 <= T <= 100), then T test cases follow
each is of A single line, N and S (1 <= N <= 16, |S| <= 100000)


Output Format:
for every test case , If there are way(s) to insert operators, output "Possible", otherwise outputs "Impossible".


Sample Input:
4 10 55 9 5 5 6 1 10000


Sample Output:
Possible Possible Impossible Impossible


Notes:
in the first test case : 55=1+2+3+4+5+6+7+8+9+10
in the second test case : 5=1+2-3+4+5+6+7-8-9
in the third case it's impossible to reach 6





Added by: muaz.32
Added at: 2015-03-13 13:00:00 UTC
Time Limit: 3 seconds
Partial score: No
Source:DCPC training 2015