#include <stdio.h>
#define Nmax 50002

int S[Nmax];
int N,T;

int main(){
	int i,x,top;
	freopen("nivele.in","r",stdin);
	freopen("nivele.out","w",stdout);
	for(scanf("%d",&T); T; --T){
		scanf("%d",&N); top=0;
		for(i=1;i<=N;++i){
			scanf("%d",&x);
			while( S[top] == x ) --top,--x;
			S[++top]=x;
		}
		if( top == 1 && S[top]==1 ) printf("DA\n");
		else printf("NU\n");
	}
	fclose(stdin); fclose(stdout);
	return 0;
}