#P2097. IncreaseSequence

IncreaseSequence

You have an array A with N elements.
Your goal is to change it into an array  that contains each number from 1 to N exactly once. The change will consist of zero or more steps. In each step, you may pick an arbitrary element of A and increase its value by k. You may pick the same element multiple times. Note that you are not allowed to decrease the value of any element.

Input

There are multiple cases.
For each input case, the first line contains two integers N and k ,the second line contains N intergers A[i]
(i=0,1,2,…,N-1).
(1≤N,A[i]≤50,1≤k≤10)

Output

Print “POSSIBLE”if you can achieve your goal, print “IMPOSSIBLE” otherwise.

Sample Input

5 2
1 2 3 3 5
4 3
1 4 3 2

Sample Output

IMPOSSIBLE
POSSIBLE

HINT

Source