#include <fstream>

using namespace std;
int t,n,i,u,v[50001],s[50001];
ifstream fin ("nivele.in");
ofstream fout ("nivele.out");

int main (){

    fin>>t;
    for (;t--;){
        fin>>n;
        for (i=1;i<=n;i++)
            fin>>v[i];
        u = 1;
        s[u] = v[1];
        for (i=2;i<=n;i++){
            s[++u] = v[i];
            while (u > 1 && s[u] == s[u-1]){
                u--;
                s[u]--;
            }
        }
        if (u == 1 && s[u] == 1)
            fout<<"DA\n";
        else
            fout<<"NU\n";
    }


    return 0;
}