#include <stdio.h>

int main(int argc, const char * argv[])
{

    int a, b;
    
    while (scanf("%d %d\n", &a, &b) != EOF) {
        if (a >= b) {
            printf("%d\n", a - b);
        } else
            printf("%d\n", b - a);
    }
    
    return 0;
}