#include<bits/stdc++.h>
using namespace std;
int main()
{
int a;
cin>> a;
if(1<a&&a<100) cout<<"yes";
	return 0;
}


/**************************************************************
	Problem: 1641
	User: lbq001
	Language: C++
	Result: Accepted
	Time:8 ms
	Memory:2072 kb
****************************************************************/