#include <bits/stdc++.h>
using namespace std;
long long mod = 1000000007;
long long inf = 1e9;
long long a[100005], ans[100005];
int gcd(int a, int b) {
  if (a == 0) return b;
  return gcd(b % a, a);
}
void solve() {
  int n, m, l, ct = 0, ans;
  bool ok = true;
  cin >> n >> l >> m;
  for (int i = 0; i < n; i++) {
    cin >> a[i];
  }
  for (int i = 0; i + 1 < n; i++) {
    int gg = max(0ll, a[i + 1] - m);
    l += a[i] - gg;
    if (l < 0) ok = false;
  }
  cout << (ok ? "YES\n" : "NO\n");
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  int t = 1;
  cin >> t;
  while (t--) solve();
  return 0;
}
