program main

!*****************************************************************************80
!
!! vectors() should be analyzed by GDB.
!
!  Licensing:
!
!    This code is distributed under the MIT license.
!
!  Modified:
!
!    18 February 2017
!
!  Author:
!
!    John Burkardt
!
!  Parameters:
!
!    None
!
  implicit none

  call timestamp ( )
  write ( *, '(a)' ) ''
  write ( *, '(a)' ) 'VECTORS():'
  write ( *, '(a)' ) '  FORTRAN90 version'
  write ( *, '(a)' ) '  A program for analysis by GDB.'

  call vector_test ( )
!
!  Terminate.
!
  write ( *, '(a)' ) ''
  write ( *, '(a)' ) 'VECTORS:'
  write ( *, '(a)' ) '  Normal end of execution.'
  write ( *, '(a)' ) ''
  call timestamp ( )

  stop
end
subroutine vector_test ( )

!*****************************************************************************80
!
!! VECTOR_TEST sets up some arrays, and calls VECTOR_PRINT and VECTOR_CHANGE.
!
!  Licensing:
!
!    This code is distributed under the MIT license.
!
!  Modified:
!
!    18 February 2017
!
!  Author:
!
!    John Burkardt
!
  implicit none

  integer a(10)
  integer, allocatable :: b(:)
  integer c(1)
  integer i
  integer n

  do i = 1, 10
    a(i) = 100 + i
  end do

  allocate ( b(1:10) )
  do i = 1, 10
    b(i) = 200 + i
  end do

  c(1) = 301

  n = 10

  call vector_print ( a, b, c, n )

  call vector_change ( a, b, c )

  deallocate ( b )

  return
end
subroutine vector_print ( a, b, c, n )

!*****************************************************************************80
!
!! VECTOR_PRINT creates the heap array D, then prints A, B, C and D.
!
!  Discussion:
!
!    C is an array of size 1, but this function "thinks" it has size 10.
!
!  Licensing:
!
!    This code is distributed under the MIT license.
!
!  Modified:
!
!    18 February 2017
!
!  Author:
!
!    John Burkardt
!
!  Parameters:
!
!    Input, integer A(10), B(10), C, N.
!
  implicit none

  integer n

  integer a(10)
  integer b(10)
  integer c(*)
  integer d(n)
  integer i

  do i = 1, 10
    d(i) = 400 + i
  end do

  write ( *, '(a)' ) ''
  write ( *, '(a)' ) '     I     A     B     C     D'
  write ( *, '(a)' ) ''
  do i = 1, 10
    write ( *, '(5i6)' ) i, a(i), b(i), c(i), d(i)
  end do

  return
end
subroutine vector_change ( a, b, c )

!*****************************************************************************80
!
!! VECTOR_CHANGE changes arrays A, B, C.
!
!  Discussion:
!
!    C is an array of size 1, but this function "thinks" it has size 10.
!
!  Licensing:
!
!    This code is distributed under the MIT license.
!
!  Modified:
!
!    18 February 2017
!
!  Author:
!
!    John Burkardt
!
!  Parameters:
!
!    Input, integer A(10), B(10), C.
!
  implicit none

  integer, parameter :: n = 10

  integer a(n)
  integer b(n)
  integer c(*)
  integer i

  do i = 1, n
    a(i) = ( a(i) - 1 ) * n + 1
    b(i) = ( b(i) - 1 ) * n + 1
    c(i) = ( c(i) - 1 ) * n + 1
  end do

  write ( *, '(a)' ) ''
  write ( *, '(a)' ) '     I     A     B     C'
  write ( *, '(a)' ) ''
  do i = 1, n
    write ( *, '(4i6)' ) i, a(i), b(i), c(i)
  end do

  return
end
subroutine timestamp ( )

!*****************************************************************************80
!
!! TIMESTAMP prints the current YMDHMS date as a time stamp.
!
!  Example:
!
!    31 May 2001   9:45:54.872 AM
!
!  Licensing:
!
!    This code is distributed under the MIT license.
!
!  Modified:
!
!    18 May 2013
!
!  Author:
!
!    John Burkardt
!
!  Parameters:
!
!    None
!
  implicit none

  character ( len = 8 ) ampm
  integer d
  integer h
  integer m
  integer mm
  character ( len = 9 ), parameter, dimension(12) :: month = (/ &
    'January  ', 'February ', 'March    ', 'April    ', &
    'May      ', 'June     ', 'July     ', 'August   ', &
    'September', 'October  ', 'November ', 'December ' /)
  integer n
  integer s
  integer values(8)
  integer y

  call date_and_time ( values = values )

  y = values(1)
  m = values(2)
  d = values(3)
  h = values(5)
  n = values(6)
  s = values(7)
  mm = values(8)

  if ( h < 12 ) then
    ampm = 'AM'
  else if ( h == 12 ) then
    if ( n == 0 .and. s == 0 ) then
      ampm = 'Noon'
    else
      ampm = 'PM'
    end if
  else
    h = h - 12
    if ( h < 12 ) then
      ampm = 'PM'
    else if ( h == 12 ) then
      if ( n == 0 .and. s == 0 ) then
        ampm = 'Midnight'
      else
        ampm = 'AM'
      end if
    end if
  end if

  write ( *, '(i2.2,1x,a,1x,i4,2x,i2,a1,i2.2,a1,i2.2,a1,i3.3,1x,a)' ) &
    d, trim ( month(m) ), y, h, ':', n, ':', s, '.', mm, trim ( ampm )

  return
end