#include<fstream>
using namespace std;
ifstream fin("nivele.in");
ofstream fout("nivele.out");
int T,i,j,n,varf,t,x;
int s[50005];
int main(){
    fin>>T;
    for(t=1;t<=T;t++){
        fin>>n;
        varf=0;
        for(i=1;i<=n;i++){
            fin>>x;
            if(x==s[varf]){
                s[varf]=x-1;
                while(s[varf]==s[varf-1]){
                    varf--;
                    s[varf]--;
                }
            }
            else
                s[++varf]=x;
        }
        if(varf==1 && s[varf]==1)
            fout<<"DA\n";
        else
            fout<<"NU\n";
    }
    return 0;
}