#include<stdio.h>
long t,n,i,l,a[50005],st[50005],f;
int main()
{
 freopen("nivele.in","r",stdin);
 freopen("nivele.out","w",stdout);
 scanf("%ld",&t);
 for(;t;--t)
    {scanf("%ld",&n);
     for(i=1;i<=n;++i)
        {scanf("%ld",&a[i]);
         if(a[i]!=st[l])st[++l]=a[i];
         else{--l;st[l]--;}}
      if(st[1]==1&&l==1)printf("DA\n");
      else printf("NU\n");
     }
 return 0;
}