#include<bits/stdc++.h>
using namespace std;
int main(){
	int a;
	cin>>a;
	if(a>1){
		if(a<100){
			cout<<"yes";
		} 
	}
	 
	return 0;
}
/**************************************************************
	Problem: 1641
	User: linmiaoling
	Language: C++
	Result: Accepted
	Time:8 ms
	Memory:2072 kb
****************************************************************/