#include <iostream>
#include <fstream>

#define N 50001

using namespace std;

ifstream fin("nivele.in");
ofstream fout("nivele.out");

int T, n, nr, v[N];

int main()
{
    fin>>T;
    for(int i=1;i<=T;i++)
    {
        fin>>nr;
        int p=0;
        for(int j=1;j<=nr;j++)
        {
            fin>>v[++p];
            if(p>=2)
            {
                while(p>=2 and v[p]==v[p-1])
                {
                    p--;
                    v[p]--;
                }
            }
        }
        if(p==1 and v[p]==1)
            fout<<"DA"<<endl;
        else
            fout<<"NU"<<endl;
    }
    fin.close();
    fout.close();
    return 0;
}