#include <iostream>
#include <fstream>


using namespace std;

ifstream f("colier.in");
ofstream g("colier.out");

int n, x, nr;
char margele[100005];

void aranjare()
{
    nr=0;
    f >> x;
    f >> margele;
    for (int i=0; i<x; i++)
    {
        if (margele[i]=='0')
            nr++;
    }
    if (x==1 && margele[0]=='1')
        g << "DA" <<endl;
    else if (x==1 && margele[0]=='0')
        g << "NU" << endl;
    else if ((x==2 && margele[0]=='1' && margele[1]=='0')||(x==2 && margele[0]=='0' && margele[1]=='1'))
        g << "DA" << endl;
    else if (nr%2==1)
        g << "DA" << endl;
    else if (nr%2==0)
        g << "NU" << endl;
}

int main()
{
    f >> n;
    for (int i=0; i<n; i++)
    {
        aranjare();
    }
    return 0;
}