#include <bits/stdc++.h>
using namespace std;
int main() {
  int t;
  cin >> t;
  while (t--) {
    int n, i, flag = 0, p;
    cin >> n;
    int arr[n];
    for (i = 0; i < n; i++) cin >> arr[i];
    sort(arr, arr + n);
    for (i = 0; i < n - 1; i++) {
      p = abs(arr[i] - arr[i + 1]);
      if (p > 1) {
        flag = 1;
        cout << "NO" << endl;
        break;
      }
    }
    if (flag == 0) cout << "YES" << endl;
  }
  return 0;
}
