[文件读写] fortran 如何删除文本中的重复行

Program www_fcode_cn
  Implicit None
  Integer , parameter :: N = 2000 ! 2000 行
  Character(len=256) :: cList(N) , c  
  integer :: i , k , io
  Open( 12 , File = "list.txt" ) !// 输入文件
  Open( 13 , File = "output.txt" ) !// 输出文件
  read( 12 , '(a256)' ) cList(1)
  write(13,*) trim(cList(1))
  k = 1
  Do i = 2 , N
    read( 12 , '(a256)' , iostat = io ) c
    if ( io /= 0 ) exit
    if ( all(cList(:k)/=trim(c)) ) then
      write(13,*) Trim( c )
      k = k + 1
      cList(k) = c
    end if
  End Do
  Close( 12 )
  Close( 13 )
End Program www_fcode_cn