#include <bits/stdc++.h>
using namespace std;
const int maxn = 1e5 + 10;
int a[105];
int main() {
  int T;
  scanf("%d", &T);
  while (T--) {
    int n, m, k;
    scanf("%d %d %d", &n, &m, &k);
    for (int i = 1; i <= n; i++) scanf("%d", &a[i]);
    bool ff = true;
    for (int i = 1; i <= n - 1; i++) {
      int nd = max(0, a[i + 1] - k);
      if (a[i] + m < nd) {
        ff = false;
        break;
      } else if (a[i] + m >= nd)
        m += a[i] - nd;
    }
    if (ff)
      printf("YES\n");
    else
      printf("NO\n");
  }
  return 0;
}
