#include
#include
using namespace std;
int main()
{
  int tm1,ts1,tm2,ts2,dm1,ds1,dm2,ds2;
  cin>>tm1>>ts1>>tm2>>ts2>>dm1>>ds1>>dm2>>ds2;
  int tufi_sekundi=(tm1*60+ts1)+(tm2*60+ts2);
  int dvojce_sekundi=(dm1*60+ds1)+(dm2*60+ds2);
  int m,s;
    if(tufi_sekundi>dvojce_sekundi){
        cout<<"D"<