#include <bits/stdc++.h>
using namespace std;
int main() {
  int t, g = 0;
  cin >> t;
  for (int i = 0; i < t; i++) {
    vector<int> p;
    int n, x;
    g = 0;
    cin >> n;
    if (n == 1) {
      cin >> x;
      cout << "YES" << endl;
      continue;
    }
    for (int l = 0; l < n; l++) {
      int k;
      cin >> k;
      p.push_back(k);
    }
    sort(p.begin(), p.end());
    for (int j = 0; j < p.size() - 1; j++) {
      if (abs(p[j] - p[j + 1]) > 1) {
        cout << "NO" << endl;
        g = 1;
        break;
      }
    }
    if (g == 0) cout << "YES" << endl;
  }
  return 0;
}
