# include <fstream>
using namespace std;
ifstream fin("nivele.in");
ofstream fout("nivele.out");
int s[50010],n,t,x,q,i,u;
int main () {
    fin>>t;
    for(q=1;q<=t;q++){
        fin>>n>>s[1];
        u=1;
        for(i=2;i<=n;i++){
            fin>>x;
            while(x==s[u]){
                x--;
                u--;
            }
            s[++u]=x;
        }
        if(u==1&&s[1]==1)
            fout<<"DA\n";
        else
            fout<<"NU\n";
    }
    return 0;
}