#include <bits/stdc++.h>
using namespace std;
int main() {
  int t;
  cin >> t;
  while (t--) {
    int n;
    cin >> n;
    int arr[n];
    for (int i = 0; i < n; i++) {
      cin >> arr[i];
    }
    sort(arr, arr + n);
    bool f = true;
    for (int j = 1; j < n; j++) {
      int diff = abs(arr[j] - arr[j - 1]);
      if (diff > 1) {
        f = false;
      }
    }
    if (f) {
      cout << "YES\n";
    } else {
      cout << "NO\n";
    }
  }
}
