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