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