Timus_1877

//Timus 1877
#include <iostream>
using namespace std;
int main()
{
    int a, b, answ=0;
    cin >> a >> b;
    if(a==0 || a%2==0) answ=1;
    if(b%2!=0) answ=1;
    if(answ==0){cout<<"no";}
    else{cout<<"yes";}
    return 0;
}