#include <bits/stdc++.h>
using namespace std;
int main(){
	int a;
	cin>>a;
	if(a>1&&a<100){
	cout<<"yes";	
	}
	
	return 0;
	
}
/**************************************************************
	Problem: 1641
	User: huanghao
	Language: C++
	Result: Accepted
	Time:13 ms
	Memory:2072 kb
****************************************************************/