remove .....

// ********* Assalamualaikum****** IN the name of my Almighty****:):)***
#include<bits/stdc++.h>
using namespace std;
#define suni ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0)
#define endl "\n"
#define f(i,a,b) for(int i=a;i< b;i++)
#define ff(i,a,b) for(int i= a;i>=b;i--)
#define T int t; cin >>t; while(t--)
#define vi  vector<int>
#define vll vector<long long>
#define vs vector<string>
#define vp vector<pair
#define pii pair<int,int>
#define pb push_back
#define mk make_pair
#define b(a) a.begin(),a.end()
#define rb(a) a.rbegin(),a.rend()
#define I  int
#define ll long long
#define st string
#define C char
#define mn int main()
#define fa(u,v) for(auto u:v)
mn
{
    suni;
    T
    {
        I n,p;
        cin>>n;
        vi v(n);
        vi :: iterator it;
        f(i,0,n)  cin>>v[i];
        sort(b(v));
        f(i,0,n-1){
            if(abs(v[i]-v[i+1])<=1)
             it=i-1;
            v.erase(it);
        }
        if(v.size()>1) cout<<"NO"<<endl;
        else cout<<"YES"<<endl;
    }
    }
//*******Happy Coding*******???******