#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using ull = unsigned long long;
ll mod = 1000000007;
ll goto_varible = 0;
class Debug {
 public:
  void debug(ll x) { cout << x << "\n"; }
  void debug(char x) { cout << x << "\n"; }
  void debug(ll a[], ll n) {
    for (ll i = 0; i < n; ++i) cout << a[i] << " ";
    cout << "\n";
  }
  void debug(vector<ll> a, ll n) {
    for (ll i = 0; i < n; ++i) cout << a[i] << " ";
    cout << "\n";
  }
  void debug(deque<ll> a, ll n) {
    for (ll i = 0; i < n; ++i) cout << a[i] << " ";
    cout << "\n";
  }
  void debug(map<ll, ll> a) {
    for (auto it = a.begin(); it != a.end(); it++)
      cout << it->first << " " << it->second << "\n";
  }
  void debug(set<ll> second) {
    for (auto it = second.begin(); it != second.end(); it++) cout << *it << " ";
    cout << "\n";
  }
};
int main() {
  Debug D;
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
  int t;
  cin >> t;
  while (t--) {
    ll n;
    cin >> n;
    ll a[n];
    for (ll i = 0; i < n; cin >> a[i++])
      ;
    sort(a, a + n);
    ll tf = 1;
    for (ll i = 0; i < n - 1; ++i) {
      if (abs(a[i] - a[i + 1]) > 1) tf = 0;
    }
    if (tf)
      cout << "YES\n";
    else
      cout << "NO\n";
    goto start;
  start:
    goto_varible = 0;
  }
  return 0;
}
