#include<stdio.h>
#include<stack>
#define NMAX 50001
using namespace std;
FILE *f=fopen("nivele.in","r");
FILE *g=fopen("nivele.out","w");
int T,N;
int main(){
	for(fscanf(f,"%d",&T);T;--T){
		fscanf(f,"%d",&N);
		stack <int> a;
		for(int i=1;i<=N;++i){
			int x;
			fscanf(f,"%d",&x);
			while(!a.empty() && x == a.top())
				x--,a.pop();
			a.push(x);
		}
		if(a.size() == 1 && a.top() == 1)fprintf(g,"DA\n");
		else fprintf(g,"NU\n");		
	}
return 0;	
}