#include<bits/stdc++.h>
using namespace std;


int main(){
  
  while(1){
    int a,b;
    cin>>a>>b;
    if(a==0 && b==0){break;}
    if(a%2==1 && b%2==1){cout<<"no"<<endl;}
    else{cout<<"yes"<<endl;}
  }
  
  return 0;
}

