#include <fstream>
#define DIM 60010
using namespace std;

ifstream fin ("nivele.in" );
ofstream fout("nivele.out");

int N, M, i, j, K, ok, minim;
int S[DIM], x, Q, k;

void Query(int N){
     K = 0;
     for(i = 1; i <= N; i ++){
          fin >> x;
          S[++K] = x;
          while(S[K] == S[K-1])
               S[--K] = --x;
     }
     if(K == 1 && S[1] == 1)
          fout << "DA\n";
     else
          fout << "NU\n";
     return;
}

int main(){
     fin >> Q;
     for(k = 1; k <= Q; k ++){
          fin >> N;
          Query(N);
     }
     return 0;
}