URI Online Judge | 2140

Two Bills

By Joao Marcos Salvanini Bellini de Moraes, IFSULDEMINAS BR Brazil

Timelimit: 1

Gilberto is a famous sfiha vendor. However, although everyone likes his sfihas, he can only give the change with two different bills, i.e., it's not always possible to get the right change. In order to make Gil's life easier, write a program for him to check whether it's possible to give the exact change using two different bills.

Available bills: 2, 5, 10, 20, 50 and 100.

Input

The input contains an integer N representing the buy price and then an integer M representing the price paid by the costumer (N < M ≤ 104). Read input until N = M = 0.

Output

Print "possible" if it's possible to give the exact change or "impossible" if it's not.

Input Sample Output Sample

11 23
500 650
100 600
9948 9963
1 2
2 4
0 0

possible
possible
impossible
possible
impossible
impossible