bac 4/20/2022 6

#include <iostream>
#include <fstream>
using namespace std;
ifstream fin("bac.in");
int fr[1001];

int main() {
    int x, odd = 0;
    while (fin >> x) {
        fr[x]++;
    }
    for (int i = 1; i <= 1000; i++) {
        if (fr[i] % 2) {
            odd++;
        }
        if (odd == 2) {
            puts("NU");
            break;
        }
    }
    if (odd != 2) {
        puts("DA");
    }
    return 0;
}