#include <fstream>
#include <vector>
using namespace std;
 
ifstream F("nivele.in");
ofstream G("nivele.out");
 
int T,N,A;
vector< int > V;
 
int main()
{
    F>>T;
    while ( T-- )
    {
        F>>N;
        while ( N-- )
        {
            F>>A;
            while ( V.size() && V.back()==A )
                V.pop_back(), --A;
            V.push_back( A );
        }
        if ( V.size()==1 && V.back()==1 ) 
            G<<"DA\n"; else G<<"NU\n";
        while ( V.size() ) 
            V.pop_back();
    }
}