#include<bits/stdc++.h> 
using namespace std;
int main(){
    int n;
	cin>>n;
	if(n>=90){
		cout<<"yes"; 
	}else{
		cout<<"no";
	}
} 
/**************************************************************
	Problem: 1301
	User: yangjunwen
	Language: C++
	Result: Wrong Answer
****************************************************************/