#include <queue>
#include <vector>
#include <stack>
#include <string>
#include <cstdio>
#include <math.h>
#include <cstdlib>
#include <string.h>
#include <iostream>
#include <fstream>
#include <algorithm>
using namespace std;
#define LL long long
#define PI acos(-1.0)
#define FRE freopen("c:\\users\\nitlian\\desktop\\input.txt","r",stdin)
#define FF freopen("c:\\users\\nitlian\\desktop\\output.txt", "w", stdout)
#define N 510
#define M 100100
#define inf 1000000000
int main() {
	int a, b;
	while (scanf ("%d%d", &a, &b), a+b) {
		if ((a&1) && (b&1) ) puts("no");
		else puts("yes");
	}
}