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

int main() {
    int N;
    long long S, B;
    cin >> N >> S >> B;
    vector<long long> H(N);
    for (int i = 0; i < N; i++) {
        cin >> H[i];
    }
    long long s = S; //, h = H[0];;
    for (int i = 0; i < N - 1; i++) {
        long long dh = H[i + 1] - H[i];
        s -= (dh + B - 1) / B;
        if (s < 0) {
            cout << "No\n";
            exit(0);
        }
        s = S;
    }
    cout << "Yes\n";
    return 0;
}