# include <stdio.h>
# include <queue>

using namespace std;

# define input "nivele.in"
# define output "nivele.out"

# define max 50001

int a[max];
int n,T,i,x;
int dr;

int main()
{
    freopen(input, "r", stdin);
    freopen(output, "w", stdout);
    
    scanf("%d",&T);
    
    while(T--)
    {
        scanf("%d",&n);
        dr = 0;
        for(i = 1; i <= n; i++)
        {
              scanf("%d",&x);
              if(!dr)  {a[++dr] = x;continue;}
              
              while(a[dr] == x && dr)  dr--,x--;
              a[++dr] = x;
        }
        if(dr == 1 && a[dr] == 1) printf("DA\n");
        else   printf("NU\n");
    }
    
    return 0;
}