#include <bits/stdc++.h>
using namespace std;
int arr[51];
int main() {
  int test_case;
  cin >> test_case;
  while (test_case--) {
    int n;
    vector<int> v;
    cin >> n;
    int tmp;
    for (int i = 0; i < n; i++) {
      cin >> tmp;
      v.push_back(tmp);
    }
    if (n == 1) {
      cout << "YES" << endl;
    } else {
      sort(v.begin(), v.end());
      bool ans = true;
      for (int i = 0; i < v.size() - 1; i++) {
        if (abs(v[i] - v[i + 1]) > 1) {
          ans = false;
          break;
        }
      }
      if (ans)
        cout << "YES" << endl;
      else
        cout << "NO" << endl;
    }
  }
  return 0;
}
