#include <cstdio>
#include <stack>

using namespace std;

#define NMAX 50050

int V[NMAX], top, t, n, i, x;

int main () {
	
	freopen ("nivele.in", "r", stdin);
	freopen ("nivele.out", "w", stdout);
	
	scanf ("%d", &t);
	
	while (t--) {
		
		scanf ("%d ", &n); 
		
		for (i = 1; i <= n; i++) {
			scanf ("%d", &x); top = 0;
			
			while (V[top] == x) top--, x--;
			V[++top] = x;
		}
		
		if (top == 1 && V[top] == 1) printf ("DA\n");
		else printf ("NU\n");
	}
	
	return 0;
}