#include <stdio.h>
#include <math.h>

long long int f(int n, int m) {
    long long int i, j, k, l;

    i = 1;
    j = n+m;    // when n=0
    k = n+m;    // when n=1;
    while(i < n) {
        l = k + (j >> 1);
        j = k;
        k = l;
        i++;
    }
    return k;
}

int main(int argc, char *argv[]) {
    long long int answer;
    int n = atoi(argv[1]);
    int m = atoi(argv[2]);
    
    answer = f(n,m);
    printf("%lld\n", answer);
    return 1;
}