#include <fstream>
#include <stack>

using namespace std;

int t, n;
stack<int> d;

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

	fin >> t;


	while (t--)
	{
		fin >> n;
		for (int i = 1, aux; i <= n; ++i)
		{
			fin >> aux;
			while (!d.empty() && d.top() == aux && aux >= 1)
			{
				d.pop();
				--aux;
			}
			d.push(aux);
		}

		if (d.size() == 1 && d.top() == 1)
			fout << "DA\n";
		else
			fout << "NU\n";

		while (!d.empty())
			d.pop();
	}


	fin.close();
	fout.close();
}