#include <bits/stdc++.h>
using namespace std;
const int maxn = 1e5 + 50;
const int maxm = 1e5 + 50;
const long long inf = 0x7fffffff;
int info[maxn];
int t, n, m;
void init() {}
int main() {
  init();
  scanf("%d", &t);
  while (t--) {
    scanf("%d", &n);
    for (int i = 0; i < n; i++) {
      scanf("%d", &info[i]);
    }
    sort(info, info + n);
    bool flag = 0;
    for (int i = 0; i < n - 1; i++) {
      if (abs(info[i] - info[i + 1]) > 1) flag = 1;
    }
    if (flag)
      puts("NO");
    else
      puts("YES");
  }
  return 0;
}
