#include<bits/stdc++.h>
using namespace std;

int main(){
	int n;
	cin>>n;
	if(n>=90){
		cout<<"yes";
	}
	
	}
	
/**************************************************************
	Problem: 1301
	User: linzihang
	Language: C++
	Result: Accepted
	Time:8 ms
	Memory:2072 kb
****************************************************************/