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

int main(){
    int a,b,c,e;
    cin >> a >> b >> c;
    e=(a%b!=0)?a/b+1:a/b;
    e=e*2/3;
    if(a>e*c) cout << "NO" << endl;
    else cout << "YES" << endl;
    
    return 0;
}