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