#include<bits/stdc++.h> using namespace std; int main() { /**char a; cin>>a; if(a == 'Y'){ cout<<'A'; }else { if(a == 'Z'){ cout<<'B'; }else{ cout<<char(a+2) ; } }**/ int a; cin>>a; if(a>=60){ cout<<"YES"; }else { cout<<"NO"; } return 0; }