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

int main()
{
int N;
int M;

	cin >> N;
	cin >> M;

	if( N == 1 && M == 1 )
		cout << "YES" << endl;
	else if( N == 1 || M > 2 )
		cout << "NO" << endl;
	else if( N > 2 || M == 1 )
		cout << "NO" << endl;
	else if( N % 2 == 1 && M % 2 == 1 )
		cout << "NO" << endl;
	else
		cout << "YES" << endl;

	return 0;
}