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