#include<fstream>
using namespace std;
int i,vf,v[101010],T,N,x;
int main()
{ifstream q("nivele.in");
ofstream w("nivele.out");
q>>T;
while(T--)
   {q>>N;
   vf=0;
   for(i=1;i<=N;++i)
     {q>>x;
     while(v[vf]==x&&vf>=1)
        {--vf;
        --x;}
     v[++vf]=x;}
   if(vf==1&&v[vf]==1)
    w<<"DA";
   else
    w<<"NU";
   w<<"\n";}}