#include<stdio.h>
#include<vector>
#define nmax 50000
using namespace std;
int level[nmax];
int t,n;
int main()
{
	freopen("nivele.in","r",stdin);
	freopen("nivele.out","w",stdout);
	scanf("%d",&t);
	for(;t;t--)
	{
		memset(level,0,sizeof(level));
		scanf("%d",&n);
		int i=0,x;
		for(;n;n--)
		{
			scanf("%d",&x);
			if(x==level[i])
			{
				i--;
				level[i]--;
			}
			else
			{
				i++;
				level[i]=x;
			}
		}
		if(i==1&&level[i]==1)
			printf("DA\n");
		else
			printf("NU\n");
	}
	return 0;
}