#include <bits/stdc++.h>
using namespace std;
int main() {
  int t, n;
  cin >> t;
  while (t--) {
    cin >> n;
    int a[n];
    for (int i = 0; i < n; i++) {
      cin >> a[i];
    }
    sort(a, a + n);
    int flag = 0;
    for (int i = 0; i < n - 1; i++) {
      if ((a[i + 1] - a[i]) > 1 || (a[i + 1] - a[i]) < -1) {
        flag = 1;
      }
    }
    if (flag == 1) {
      cout << "NO"
           << "\n";
    } else {
      cout << "YES"
           << "\n";
    }
  }
  return 0;
}
