#include<iostream>
using namespace std;
int main ()
{
    int n,a,b,c;
    cin>>n;
    a=n/100;
    b=n/10%10;
    c=n%10;
    if(a==b && b==c && a==c)
    {
        cout<<"da";
    }
    else
    {
        cout<<"nu";
    }
    return 0;
}