#include <iostream>

using namespace std;

int main()
{
    string s1, s2;
    cin>>s1>>s2;
    if((s1[0]==s2[0]) || (s1[1]==s2[1]))
        cout<<"da";
    else{
        if(abs(s1[0]-s2[0]) == abs(s1[1]-s2[1]))
            cout<<"da";
        else
            cout<<"ne";
    }
    return 0;
}