#include <bits/stdc++.h>
using namespace std;

int main()
{
	int t;
	cin >> t;

	while (t--)
	{
		int N;
		cin >> N;

		int arr[N];

		for (int n=0; n<N; n++)
		{
			cin >> arr[n];
		}

		sort(arr, arr+N);
		bool flag = true;

		for (int n=1; n<N; n++)
		{
			if (arr[n] - arr[n-1] != 1)
			{
				
				flag = false;
				break;
			}
		}

		if (flag)
		{
			cout << "YES";
		}
		else
		{
			cout << "NO";
		}

		cout << endl;
	}

	return 0;
}