#include<stdio.h>
#define nmax 50001

int st[nmax],vf;

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