#include <iostream>

using namespace std;

int main() {
	int a, b, c;
	cin >> a >> b >> c;
	int normalCount = (a + (b - 1)) / b;
	int specialCount = normalCount * 2 / 3;
	bool enough = (c * specialCount >= a);
	cout << (enough ? "YES" : "NO") << endl;
	return 0;
}