// Problem#: 1000
// Submission#: 2424748
// The source code is licensed under Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License
// URI: http://creativecommons.org/licenses/by-nc-sa/3.0/
// All Copyright reserved by Informatic Lab of Sun Yat-sen University
#include <stdio.h>
int main()
{
    int A,B;
    scanf("%d%d",&A,&B);
    printf("%d\n",A-B);
    return 0;
}