#include<bits/stdc++.h>
using namespace std;
int main(){
    int n;
    cin>>n;
    if(n>=90){
    	cout<<"yes";
	}
	if(n<90){
		cout<<" ";
	}
}
/**************************************************************
	Problem: 1301
	User: toughuatao1
	Language: C++
	Result: Accepted
	Time:7 ms
	Memory:2072 kb
****************************************************************/