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

int main() {
  int t;
  cin >> t;
  for (int i=0; i<t; i++){
    int n, m;
    cin >> n >> m;
    vector<int> a(n+1);
    a.at(0) = m;
    for (int j=1; j<n+1; j++){
      cin >> a.at(j);
    }
    int x = 0;
    bool flag = true;
    for (int j=1; j<n+1; j++){
      if (a.at(j) < x || a.at(j) - x > a.at(j-1)){
        flag = false;
        break;
      } else {
        x = a.at(j-1) - (a.at(j) - x);
      }
    }
    cout << (flag? "Yes" : "No") << endl;
  }
}