#include <bits/stdc++.h>
using namespace std;
void sfsf() {
  ios::sync_with_stdio(0);
  cin.tie(nullptr);
  cout.tie(nullptr);
}
const int mxn = 2e5 + 5, N = 8e1 + 5, mod = 1e9 + 7, inf = 0x3f,
          mod2 = 999119999, mod3 = 1000992299, pow1 = 31, pow2 = 53;
int main() {
  sfsf();
  int t;
  cin >> t;
  while (t--) {
    int n;
    cin >> n;
    vector<int> vi(n);
    for (int i = 0; i < n; i++) cin >> vi[i];
    sort(vi.begin(), vi.end());
    bool flag = true;
    for (int i = 1; i < n; i++)
      if (abs(vi[i] - vi[i - 1]) > 1) flag = false;
    if (flag)
      cout << "YES" << endl;
    else
      cout << "NO" << endl;
  }
  return 0;
}
