#include <bits/stdc++.h>
using namespace std;
const int INF = 1e8 + 1;
void solve() {
  int n;
  cin >> n;
  vector<int> nums(n);
  for (int i = 0; i < n; i++) cin >> nums[i];
  sort(nums.begin(), nums.end());
  bool ok = true;
  for (int i = 0; i < n - 1; i++) {
    if ((abs(nums[i] - nums[i + 1])) > 1) {
      ok = false;
      break;
    }
  }
  if (ok)
    cout << "YES" << endl;
  else
    cout << "NO" << endl;
}
int main() {
  int t;
  cin >> t;
  while (t--) {
    solve();
  }
}
