program lab_1_2
    use Environment
    implicit none

    integer, parameter                 :: NAME_LEN = 15, DATE_LEN = 4,&
                                          SERV_LEN = 3, REG_LEN = 1, SEX = 1
    integer, parameter                 :: len = 6

    character(kind=CH_), allocatable   :: chName(:,:), Date(:,:),&
                                          Serv(:,:), Reg(:,:), Gen(:,:)
    character(kind=CH_), parameter  :: s="S", p="P", yes = "yes"
    allocate(chname(len, Name_len), Date(len, Date_len),&
             serv(len, serv_len), reg(len, reg_len), gen(len, sex))

    call Read_list(input, chname, date, serv, reg, gen)

    call Write_list(output, chname, date, serv, reg, gen,&
                     "list before", "rewind", len)
    call Sort_list (chname, date, serv, reg, gen)

    contains
       subroutine Read_list(input, chname, date, serv, reg, gen)
         character(*) input
         character(kind=CH_), allocatable   :: chName(:,:), Date(:,:),&
                                          Serv(:,:), Reg(:,:), Gen(:,:)
         intent(in) input
         intent(inout) chname, date, serv, reg, gen

         integer in, IO, i
         character(:), allocatable :: format

         open( file = input, encoding=E_, newunit=in)
            format = "(1A15, 1A4, 1X, 1A3, 1X, 1A1, 1X, 1A1)"
            read(in, format) (chName(i,:), Date(i,:), Serv(i,:), Reg(i,:), Gen(i,:), i=1, 6)
         close(in)
        end subroutine Read_list

        subroutine Write_list ( output, chname, date, serv, reg, gen, comment, pos, len)
            character(*)      output, comment, pos
            character(kind=CH_)   :: chName(:,:), Date(:,:),&
                                     Serv(:,:), Reg(:,:), Gen(:,:)
            intent(in) output, comment, pos
            integer, intent(in)  :: len
            intent(inout) chname, date, serv, reg, gen
            integer        :: out, i , io
            character(:), allocatable :: format
            open(file=output, encoding=E_, position=pos, newunit=out)
               write(out, '(/a)') comment
               format = "(1A15, 1A4, 1X, 1A3, 1X, 1A1, 1X, 1A1)"
               do i=1, len
                  write(out, format) chName(i,:), Date(i,:), Serv(i,:),&
                                         Reg(i,:), Gen(i,:)
               end do
            close(out)
         end subroutine Write_list


         subroutine Sort_list(chname, date, serv, reg, gen)
            character(kind=CH_) chname(:,:), date(:,:), serv(:,:),&
                                 reg(:,:), gen(:,:)

            integer              i, j
            integer, parameter   :: INDEXES(*) = [(i, i = 1, len)]

            do i=1, len
            !   if( serv(i, :) .eq. s ) then
                  print *, "got"
            !   end if
            end do

         end subroutine

end program lab_1_2