#include<iostream>
#include<algorithm>
using namespace std;

int main()
{
    int t;
    cin >> t;
    while(t--)
    {
        int n,ctr=0;
        cin >> n;
        int arr[n];
        for(int i=0;i<n;i++)
        {
            cin >> arr[i];
        }
        sort(arr,arr+n);
        for(int i=0;i<n-1;i++)
        {
            if(arr[i]+1!=arr[i+1])
            {
                ctr++;
            }
        }
        if(ctr==0)
            cout << "YES" << endl;
        else
            cout << "NO" << endl;
    }
}