#include<cstdio>
#include<cstring>
#include<iostream>
#include<algorithm>
using namespace std;
int main()
{
    int n,m;
    while(scanf("%d%d",&n,&m)!=EOF)
    {
        if(n==0&&m==0) continue;
        printf(((n&1)&&(m&1))?"no\n":"yes\n");
    }
    return 0;
}