SN2019-s3e2.cpp

#include <iostream>
using namespace std;


int main() {

        int n, i, a[21];
        cin >> n;

        for (i = 0; i < n; i++)
                cin >> a[i];

        int symmetric = 1;
        for (i = 0; i < (n - 1) / 2; i++) {
                if (a[i] != a[n - i - 1]) {
                        symmetric = 0;
                }

        }

        if (symmetric == 1)
                cout << "DA" << endl;
        else
                cout << "NU" << endl;

        return 0;
}