using System;
using static System.Console;
using System.Linq;
using System.Collections.Generic;

class Program
{
    static int NN => int.Parse(ReadLine());
    static int[] NList => ReadLine().Split().Select(int.Parse).ToArray();
    static int[][] NArr(long n) => Enumerable.Repeat(0, (int)n).Select(_ => NList).ToArray();
    public static void Main()
    {
        Solve();
    }
    static void Solve()
    {
        var c = NList;
        var (n, s, b) = (c[0], c[1], c[2]);
        var h = NList;
        var j = (long)s * b;
        var current = h[0] + j;
        for (var i = 1; i < n; ++i)
        {
            if (current < h[i])
            {
                WriteLine("No");
                return;
            }
            current = Math.Max(current, h[i] + j);
        }
        WriteLine("Yes");
    }
}