//#include <iostream>
#include <fstream>
using namespace std;
long long cur[50005];
int main()
{
    ifstream cin("nivele.in");
    ofstream cout("nivele.out");
    int t;
    cin>>t;
    while(t--){
        int n,k=0,a;
        cin>>n;
        for(int i=1;i<=n;i++){
            cin>>a;
            cur[++k]=a;
            while(k!=1 and cur[k]==cur[k-1]){
                cur[k-1]--;
                k--;
            }
        }
        if(k==1 and cur[k]==1){
            cout<<"DA\n";
        }
        else
            cout<<"NU\n";
    }
    return 0;
}