#include<bits/stdc++.h>
using namespace std;
using LL = long long;
using ULL = unsigned long long;
#define rep(i,n) for(int i=0; i<(n); i++)

int main() {
	int N, K, T; cin >> N >> K >> T;
	bool ok = (abs(N) + K - 1) / K <= T;
	cout << (ok ? "Yes" : "No") << endl;
	return 0;
}