/*
入力 validation 付き
*/

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

int main(){
	registerValidation();
    int s = inf.readInt(100,599,"s");
    inf.readEoln();
    cout << (s < 400 ? "No" : "Yes") << endl;
	inf.readEof();
	return 0;
}