anchor.diff:    subroutine swap(x, vw, vl, vt, vn, it1, it2)
   
       ! Swaps positions related to items it1 and it2 in real vectors vw,
  -    ! vl and integer vector vt, vn
  +    ! vl and integer vectors vt, vn
   
       implicit none
   
  
positive.code: 
    ! PRIVATE PARAMETERS
  
    ! Maximum number of items for each type
    ! integer, parameter :: maxitems(4) = (/ 66, 64, 36, 36 /)
    ! Type of container for each type of item
    ! integer, parameter :: conttype(4) = (/ 2 ,  1,  1, 1 /)
  
    ! Maximum number of items for each type
    ! integer, parameter :: maxitems(4) = (/ 121, 64, 64, 36 /)
    ! Type of container for each type of item
    ! integer, parameter :: conttype(4) = (/   1,  1,  1,  1 /)
    ! Configuration file: containers' dimensions
    character(80), parameter :: c_filename = 'containers.txt'
    ! Configuration file: items' dimensions
    character(80), parameter :: i_filename = 'items.txt'
    ! Statistics information file
    character(80), parameter :: stats_filename = 'stats.csv'
  
  
    ! PRIVATE SCALARS
  
  
negative.code:     ! LOCAL SCALARS
      integer :: i
      real(8) :: scale
  
      ! Try to find a reasonable scale for drawing
  
      scale = max(1.0D-4, min(1.0D0, 30.0D0 / maxval(x(1:nItems))))
  
  