#include <bits/stdc++.h>
using namespace std;
void test() {
  int n, f, a[50];
  cin >> n;
  f = n;
  for (int i = 0; i < n; i++) {
    cin >> a[i];
  }
  sort(a, a + n);
  for (int i = 0; i < n - 1; i++) {
    if (abs(a[i + 1] - a[i]) > 1) {
      cout << "NO\n";
      return;
    }
  }
  cout << "YES\n";
}
int main() {
  int t;
  cin >> t;
  while (t--) test();
  return 0;
}
