#include <bits/stdc++.h>
using namespace std;
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  int t;
  cin >> t;
  while (t--) {
    int n;
    cin >> n;
    int ar[n];
    for (int i = 0; i < n; ++i) cin >> ar[i];
    int d;
    sort(ar, ar + n);
    bool yes = true;
    for (int i = 1; i < n; ++i) {
      d = abs(ar[i] - ar[i - 1]);
      if (d > 1) {
        cout << "NO\n";
        yes = false;
        break;
      }
    }
    if (yes) cout << "YES\n";
  }
  return 0;
}
