题解

#include<bits/stdc++.h>
using namespace std;
int main(){
int a,b;
cin>>a>>b;
if(a0&&b0){
cout<<"yes";
return 0;
}
if(a1&&b-1){
cout<<"yes";
}
else if(a1&&b1){
cout<<"yes";
}
else if(a==-1&&b==-1){
cout<<"yes";
}
else if(a==-1&&b==1){
cout<<"yes";
}
else{
cout<<"no";
}
return 0;
}