#include<stdio.h>
int main()
{
    long long int a,b,c;
    while(scanf("%lld%lld",&a,&b)==2)
    {
        if(a>b)
        {
            printf("%lld\n",a-b);
        }
        else
        {
            printf("%lld\n",b-a);
        }
    }
    return 0;
}