#include <fstream>
using namespace std;

ifstream f("nivele.in");
ofstream g("nivele.out");

int N, T, S[50001];
char *P[3]; 

void second()
{
	f >> N;
	S[0] = 0;
	for (int i = 1; i <= N; i++)
	{
		f >> S[++S[0]];
		while (S[0] > 1 && S[S[0]] == S[S[0]-1])
			S[--S[0]]--;
	}
	if (S[0] == 1 && S[1] == 1)
		*P = "DA\n";
	else
		*P = "NU\n";
	g << *P;
}

int main()
{
	f >> T;
	while (T--)
		second();	
	return 0;
}