O. Osmos V
time limit per test
1 second
memory limit per test
1024 megabytes
input
standard input
output
standard output

Malu is on a journey to the distant planet Osmos V aboard her spaceship, the HB-20000. Traveling at a speed close to the speed of light, Malu cannot determine her exact position in the universe. However, she knows that the total duration of the trip is exactly $$$X$$$ years and that $$$Y$$$ years have already passed.

How many years are left until Malu reaches her destination?

Input

The input consists of two lines.

The first line contains the integer $$$X$$$ $$$(1 \le X \le 10^9)$$$, representing the total duration of the trip in years.

The second line contains an integer $$$Y$$$ $$$(0 \le Y \le X)$$$, representing how many years have already passed.

Output

The output must contain a single integer, representing the number of years remaining until Malu reaches her destination.

Examples
Input
10
5
Output
5
Input
1
1
Output
0
Input
100000
4312
Output
95688