#include <stdio.h>

#define NMAX 50010

int N, T;

int nst;
int st[NMAX];

int main()
{
	int i, q;

	freopen("nivele.in", "r", stdin);
	freopen("nivele.out", "w", stdout);

	for (scanf("%d", &T); T; --T) {
		scanf("%d", &N);
		nst = 0;

		for (i = 1; i <= N; i++) {
			scanf("%d", &q);
			st[++nst] = q;

			while (nst >= 2 && st[nst - 1] == st[nst]) st[--nst]--;
		}

		if (!(nst == 1 && st[1] == 1)) printf("NU\n");
		else printf("DA\n");
	}

return 0;
}