#include <cstdio>
#define DN 50002

int s[DN];

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