import std.algorithm;
import std.array;
import std.conv;
import std.math;
import std.range;
import std.stdio;
import std.string;
import std.typecons;

int readint() {
    return readln.chomp.to!int;
}

int[] readints() {
    return readln.split.map!(to!int).array;
}

void main() {
    while (true) {
        auto ab = readints;
        int a = ab[0], b = ab[1];
        if (a == 0 && b == 0)
            break;

        if (a % 2 == 1 && b % 2 == 1) {
            writeln("no");
        }
        else {
            writeln("yes");
        }
    }
}