#include <bits/stdc++.h>
using namespace std;
const int N = 1e5 + 10;
int T, n, a[N];
int main() {
  ios::sync_with_stdio(0);
  cin >> T;
  while (T--) {
    cin >> n;
    for (int i = 1; i <= n; i++) cin >> a[i];
    sort(a + 1, a + 1 + n);
    int f = 0;
    for (int i = 1; i <= n - 1; i++) {
      if (abs(a[i] - a[i + 1]) > 1) f = 1;
    }
    if (f == 1)
      printf("NO\n");
    else
      printf("YES\n");
  }
}
