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