#include <cstdio>
using namespace std;

int stk[50005],stp;
int n,t;

int main() {
	freopen("nivele.in","r",stdin);
	freopen("nivele.out","w",stdout);
	scanf("%d",&t);
	while (t--) {
		scanf("%d",&n);
		stp = 0;
		for (int i=1;i<=n;i++) {
			int crt; scanf("%d",&crt);
			stk[++stp] = crt;
			while (stp >= 2 && stk[stp] == stk[stp-1]) {
			    stp--; stk[stp]--;
			}
		}
		if (stp == 1 && stk[stp] == 1) printf("DA\n");
        else printf("NU\n");
	}
}