anchor.diff:    end subroutine array_swap_dp
   
     subroutine array_swap_int(arr, i, j)
  -    ! Swap values of arr(i) and arr(j)
  -
  +    ! Duplicate of array_swap_dp, but for an integer array.
       integer, intent(inout) :: arr(:)
       integer, intent(in) :: i, j
   
  
positive.code: 
    subroutine array_reverse_dp(arr)
      ! Reverse array
  
      real(dp), intent(inout) :: arr(:)
  
      integer :: i, j, n
  
negative.code:   contains
  
      subroutine partition_lomuto_int(arr, i_min, i_max, part)
        ! Duplication of partition_lomuto_dp in array_quicksort_dp, but for an
        ! integer array.
        integer, intent(inout) :: arr(:)
        integer, intent(in) :: i_min, i_max
        integer, intent(out) :: part
  