#include<bits/stdc++.h>
using namespace std;
int main(){
    int n;
    cin>>n;
    if(n>=90;){
    	cout<<"yes";
	}else cout<<" ";
    return 0;
} 
/**************************************************************
	Problem: 1301
	User: houlingqi2
	Language: C++
	Result: Compile Error
****************************************************************/