#include <bits/stdc++.h>

using namespace std;
typedef long long ll;

#define f first
#define s second

ifstream fin ("nivele.in");
ofstream fout ("nivele.out");

int n, x, t;

int main()
{
  ios_base::sync_with_stdio(false);
  cin.tie(0); cout.tie(0);
  fin >> t;
  while (t--) {
    fin >> n;
    vector<int>v;
    for (int i = 1; i <= n; i++) {
      fin >> x;
      v.push_back(x);
      while (v.size() >= 2 && v[v.size() - 2] == v.back()) {
        v.pop_back();
        v.back()--;
      }
    }
    if (v.size() == 1 && v[0] == 1) {
      fout << "DA";
    }
    else
      fout << "NU";
      fout << "\n";
  }
  return 0;
}