J. Journey for Grapes
time limit per test
1 second
memory limit per test
256 megabytes
input
standard input
output
standard output

In Miguel's beach house, there is a magic room: whoever solves the room's riddle is granted a wish. Noticing that his friend Walfrido was sad, Thawan decided to enter the room to cheer him up. His goal is to ask for a generous portion of grapes with margarine, Walfrido's favorite snack!

However, the room will only grant the wish if Thawan can solve the following problem:

Consider a regular polygon with $$$N$$$ vertices, numbered from $$$0$$$ to $$$N - 1$$$ in a clockwise direction. Thawan starts his journey at vertex $$$0$$$. In each move, he makes a jump of size $$$S$$$, advancing exactly $$$S$$$ vertices clockwise. That is, if he is currently at vertex $$$x$$$, the jump will take him to vertex $$$(x + S) \bmod N$$$.

Knowing that Thawan can continue jumping indefinitely, determine the maximum number of distinct vertices he will be able to visit along his path. Help Thawan secure Walfrido's snack!

Input

The only input line contains two integers, $$$N$$$ and $$$S$$$ ($$$1 \le S \le N \le 10^9$$$), representing the number of vertices of the polygon and the size of Thawan's jump, respectively.

Output

Print a single integer representing the number of distinct vertices Thawan can reach.

Examples
Input
2 1
Output
2
Input
14 8
Output
7