#include<bits/stdc++.h>
using namespace std;
int main()
{   
    int a,b;
    cin>>a>>b;
    if (b-a==1){
    	cout<<"Yes";
	}
	else if(b-a==9){
		cout<<"Yes";
	}
	else
	{
		cout<<"No";
	}
    return 0;
}