#include <bits/stdc++.h>
using namespace std;
int main() {
  int a, b, c, p;
  vector<int> x;
  cin >> a;
  for (int i = 0; i < a; i++) {
    cin >> b;
    bool er = false;
    for (int j = 0; j < b; j++) {
      cin >> c;
      x.push_back(c);
      p = c;
    }
    sort(x.begin(), x.end());
    for (int j = 1; j < b; j++) {
      if (x[j - 1] != x[j]) {
        if (x[j - 1] < x[j] && x[j] - x[j - 1] >= 2) er = true;
      }
    }
    x.clear();
    if (er == false)
      cout << "YES" << endl;
    else
      cout << "NO" << endl;
  }
}
