#include<stdio.h>
int t,n,i,x,u;
int st[50002];
int main()
{
	freopen("nivele.in","r",stdin);
	freopen("nivele.out","w",stdout);
	scanf("%d",&t);
	while(t--)
	{
		u=0;
		scanf("%d",&n);
		for(i=1;i<=n;i++)
		{
			scanf("%d",&x);
			while(st[u]==x)
			{
				u--;
				x--;
			}
			st[++u]=x;
		}
		printf("%s\n",(st[u]==1 && u==1)?"DA":"NU");
	}
	return 0;
}