program chess_elefant;
Var
   i, k, l, m, n : integer;
Begin
   writeln('*********Program Chess elefant*********') ;
   write('Please, enter k=') ; readln(k) ;  {entering first position}
   write('Please, enter l=') ; readln(l) ;
   write('Please, enter m=') ; readln(m) ;  {entering second position}
   write('Please, enter n=') ; readln(n) ;
   if abs(m - k) = abs(n - l) then writeln('Elefant can go this way')
   else writeln('Elefant can not go this way');
   readln;
end.