# DSLCS 2011 Number Theory. Favorites

# Gergs cake

Gerg is having a party, and he has invited his friends. **p** of them have arrived already, but **a** are running late. To occupy his guests, he tried playing some team games with them, but he found that it was impossible to divide the p guests into any number of equal-sized groups of more than one person.

Luckily, he has a backup plan - a cake that he would like to share between his friends. The cake is in the shape of a square, and Gerg insists on cutting it up into equal-sized square pieces. He wants to reserve one slice for each of the a missing friends, and the rest of the slices have to be divided evenly between the p remaining guests. He does not want any cake himself. Can he do it?

** Input**

The input will consist of several test cases. Each test case will be given as a non-negative integer **a** and a positive integer **p** as specified above, on a line. Both **a** and **p** will fit into a **32**-bit signed integer. The last line will contain "**-1 -1**" and should not be processed.

** Output**

For each test case, output "**Yes**" if the cake can be fairly divided and "**No**" otherwise.

1 3 1024 17 2 101 0 1 -1 -1

Yes Yes No Yes