integer*8::X,Y,L,step
  read*,X,Y,L
  if(X.eq.0.and.Y.ge.0) then
     step = 0
  else if(Y.ge.0) then
     step = 1
  else
     step = 2
  endif
  print '(i0)',step+(ABS(X)+L-1)/L+(ABS(Y)+L-1)/L
end program