#include <stdio.h>
#define DIM 50002
int T,nf,v,i,x,j;
int S[DIM];

int main(){
  FILE *f = fopen("nivele.in","r");
  FILE *g = fopen("nivele.out","w");
  fscanf(f,"%d",&T);
  for (i=1;i<=T;i++) {
	fscanf(f,"%d",&nf);
	fscanf(f,"%d",&S[1]);
	v = 1;
	for (j=2;j<=nf;j++) {
	  fscanf(f,"%d",&x);
	  while(S[v] == x) {
		v--;
		x--;
	  }
	  S[++v] = x;
	}
	if ((v==1)&&(S[1]==1)) {
		fprintf(g,"DA\n");
	} else {
		fprintf(g,"NU\n");
	}
  }
  fclose(f);
  fclose(g);

  return 0;
}