#include <bits/stdc++.h>

using namespace std;

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

const int DIM = 50005; 

int v[DIM];

int main() {
  int t, n;

  fin >> t;
  while ( t-- ) {
	fin >> n;
	for ( int i = 1; i <= n; ++i ) {
	  fin >> v[i];
	}
    vector<int> stk;
	for ( int i = 1; i <= n; ++i ) {
	  while ( stk.size() && stk.back() == v[i] ) {
		stk.pop_back();
		--v[i];
	  }
      stk.push_back(v[i]);
	}
	fout << (stk.size() == 1 && stk.back() == 1 ? "DA\n" : "NU\n");
  }
  fin.close();
  fout.close();
  return 0;
}