#include<fstream>
#include<vector>
#include<algorithm>
using namespace std;
ifstream fin("nivele.in");
ofstream fout("nivele.out");
int t,n,v[50005],i,ok;

int main(){
    fin>>t;
    for(;t>0;t--)
    {
        ok=0;
        fin>>n;
        for(i=1;i<=n;i++)
        {
            ok++;
            fin>>v[ok];
            while(ok>1)
            {
                if(v[ok]==v[ok-1])
                {
                    v[ok-1]--;
                    v[ok]=0;
                    ok--;
                }
                else
                    break;
            }
        }
        if(ok==1&&v[ok]==1)
            fout<<"DA\n";
        else
            fout<<"NU\n";
    }
    fin.close();
    fout.close();
    return 0;
}