#include <cstdio>
//#include <vector>
#define vv 50002

using namespace std;

int n,a[vv],s[vv],w;

void nivele()
{
    w=0;
    for (int i=1; i<=n; i++)
    {
        s[++w]=a[i];
        while (s[w]==s[w-1])
            s[--w]-=1;
    }
    if (w==1 && s[w]==1)
        printf("DA\n");
    else
        printf("NU\n");
}

void citire()
{
    freopen("nivele.in","r",stdin);
    int t;
    for (scanf("%d", &t); t; t--)
    {
        scanf("%d", &n);
        for (int i=1; i<=n; i++)
            scanf("%d", &a[i]);
        nivele();
    }
    fclose(stdin);
}

int main()
{
    freopen("nivele.out","w",stdout);
    citire();
    fclose(stdout);
    return 0;
}