#include<bits/stdc++.h> using namespace std; int x,y; int main(){ cin>>x>>y; if(x>=1&&y>=-1) cout<<"Yes"; else if(x>=1&&y>=1) cout<<"Yes"; else if(x>=-1&&y>=-1) cout<<"Yes"; else if(x>=-1&&y>=1) cout<<"Yes"; else cout<<"No"; return 0; }