#include <bits/stdc++.h>
using namespace std;
bool isPrime(int n) {
  if (n <= 1) return false;
  if (n <= 3) return true;
  if (n % 2 == 0 || n % 3 == 0) return false;
  for (int i = 5; i * i <= n; i = i + 6)
    if (n % i == 0 || n % (i + 2) == 0) return false;
  return true;
}
long long int com(long long int n, long long int a) {
  long long int result = 1;
  if (n - a < a) a = n - a;
  long long int cnt = 1;
  for (long long int i = n - a + 1; i < n + 1; i++) {
    result *= i;
    result /= cnt;
    cnt++;
  }
  return result;
}
void swap(int *xp, int *yp) {
  int temp = *xp;
  *xp = *yp;
  *yp = temp;
}
void bubbleSort(int arr[], int n) {
  int i, j;
  for (i = 0; i < n - 1; i++)
    for (j = 0; j < n - i - 1; j++)
      if (arr[j] > arr[j + 1]) swap(&arr[j], &arr[j + 1]);
}
string to_upper(string &in) {
  for (int i = 0; i < in.length(); i++)
    if ('a' <= in[i] <= 'z') in[i] &= ~(1 << 5);
  return in;
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
  ;
  long long int test, temp = 0;
  cin >> test;
  while (test > 0) {
    long long int n;
    cin >> n;
    long long int a[n];
    for (long long int i = 0; i < n; i++) {
      cin >> a[i];
    }
    sort(a, a + n);
    long long int flag = 0;
    for (long long int i = 0; i < n - 1; i++) {
      if (abs(a[i] - a[i + 1]) > 1) {
        flag = 1;
        break;
      }
    }
    if (flag)
      cout << "NO";
    else {
      cout << "YES";
    }
    cout << "\n";
    test--;
  }
}
