#include<stdio.h>
#define Nmax 50010

int st[Nmax];

int main(){

  FILE *fin = fopen("nivele.in","r"),
        *fout = fopen("nivele.out","w");
        
  int T,N,vf,val;
  fscanf(fin,"%d",&T);
  
  while(T--){
    
     fscanf(fin,"%d",&N);
     vf = 0;
     
     for(int i=0;i<N;i++){
        fscanf(fin,"%d",&val);   
        st[++vf] = val;
        
        while(vf > 1){
          if(st[vf] == st[vf-1]){
            vf--;
            st[vf] --;
          }     
          else
            break;
        }        
     }
     
      if(vf == 1 && st[vf] ==1)
        fprintf(fout,"DA\n");
      else
        fprintf(fout,"NU\n");        

  }
  
  fclose(fin);
  fclose(fout);
  return 0;
  
}