VerifDiferite

#include <iostream>
using namespace std;
long int v[501],u[10000];

int main()
{
    long int n,i,ma=-1;
    cin>>n;
    for(i=1;i<=n;++i)
        cin>>v[i],ma=max(v[i],ma),++u[v[i]];
    for(i=1;i<=ma;i++)
        if(u[i]>1)
        {
            cout<<"NU";
            return 0;
        }
    cout<<"DA";
    return 0;
}