#include<stdio.h>
long int t,nt,n,lc,i,c[50005];
int main()
{
	FILE *f,*g;f=fopen("nivele.in","r");g=fopen("nivele.out","w");
	fscanf(f,"%ld",&t);
	for(nt=1;nt<=t;nt++)
	{ fscanf(f,"%ld",&n);
	  lc=0;
	  for(i=1;i<=n;i++)
	  { lc++;fscanf(f,"%ld",&c[lc]);
	    while(c[lc]==c[lc-1])lc--;c[lc]--;
	    if(!lc)break;
	  }
	  if(lc==1&&c[lc]==1) fprintf(g,"DA\n");
	  else fprintf(g,"NU\n");
	}
	fcloseall();
	return 0;
}