#include <iostream>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <cmath>
#include <string>
#include <algorithm>
#include <vector>
#include <queue>
#include <set>
#include <map>
#include <deque>
using namespace std;

int main() {
    int a, b;
    while (2 == scanf("%d%d", &a, &b) && (a || b)) {
        puts((a % 2 && b % 2) ? "no" : "yes");
    }
    return EXIT_SUCCESS;
}