import java.util.*;

public class Main {
    public static void main(String[] args) throws Exception {
        
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        int k = sc.nextInt();
        int t = sc.nextInt();
        
        int distance = 0;
        for(int i = 0; i < t; i++) {
            distance += k;
        }
        
        if(n < 0) {
            n = -n;
        }
        
        
        if(distance >= n) {
            System.out.println("Yes");

        }else {
            System.out.println("No");
        }
    }
}