#include <bits/stdc++.h>
using namespace std;
bool check(long long n) {
  if (n != 0) {
    if ((n & (n - 1)) == 0) {
      return true;
    }
  }
  return false;
}
vector<long long> SieveOfEratosthenes(int n) {
  bool prime[n + 1];
  memset(prime, true, sizeof(prime));
  for (int p = 2; p * p <= n; p++) {
    if (prime[p] == true) {
      for (int i = p * p; i <= n; i += p) prime[i] = false;
    }
  }
  vector<long long> v;
  for (int p = 2; p <= n; p++)
    if (prime[p]) v.push_back(p);
  return v;
}
long long power(long long x, long long y) {
  long long res = 1;
  while (y > 0) {
    if (y & 1) res = res * x;
    y = y >> 1;
    x = x * x;
  }
  return res;
}
int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  cout.tie(0);
  long long t;
  cin >> t;
  while (t--) {
    long long n;
    cin >> n;
    vector<long long> a(n);
    for (int i = 0; i < n; i++) cin >> a[i];
    sort(a.begin(), a.end());
    if (n == 1)
      cout << "YES\n";
    else {
      int co = 0;
      for (int i = 0; i < a.size(); i++) {
        for (int j = i + 1; j < n; j++) {
          if (a[j] - a[i] <= 1) {
            co++;
            break;
          }
        }
      }
      if (co != n - 1) {
        cout << "NO\n";
      } else {
        cout << "YES\n";
      }
    }
  }
  return 0;
}
