# include <cstdio>
# include <stack>
 
using namespace std;
 
int n, t, i, j, a;
int main()
{
    
    freopen("nivele.in","r",stdin);
    freopen("nivele.out","w",stdout);
     
    scanf("%d",&t);
    for (i = 1; i <= t; i++)
    {
        scanf("%d",&n);
        stack<int>S;
        for (j = 1; j <= n; j++)
        {
            scanf("%d",&a);
             
            while (!S.empty() && S.top() == a)
            {
                  S.pop();
                  a--;
                  }
            S.push(a);
            }
         
        if (S.size() == 1 && S.top() == 1)
                        printf("DA\n");
                   else printf("NU\n");
        }
}