#include <stdio.h>
#include <stdlib.h>
int main(void) {
    int a, b;
    scanf("%d %d", &a, &b);

    int res = abs(a-b);
    int c;
    if(a < b)
        c = b + res;
    else
        c = a + res;
    printf("%d", c);
    return 0;
}