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