Beefy Boxes and Bandwidth Generously Provided by pair Networks
Perl: the Markov chain saw
 
PerlMonks  

Re: Re: Re: group based array sort

by Limbic~Region (Chancellor)
on Feb 19, 2004 at 22:59 UTC ( #330392=note: print w/ replies, xml ) Need Help??


in reply to Re: Re: group based array sort
in thread group based array sort

bageler,
While I really think using Sort::Tree is probably the best option, here is a purely iterative solution. It has the following requirements:

  • IDs will always be numerical
  • Root level nodes will always have a parent of 0
  • Probably a few others
    #!/usr/bin/perl use strict; use warnings; my @list = ( {id => 6, parent => 2, level => 3, name => '1234' }, {id => 2, parent => 1, level => 2, name => 'bar2' }, {id => 4, parent => 1, level => 2, name => 'asdf' }, {id => 3, parent => 1, level => 2, name => 'blah' }, {id => 1, parent => 0, level => 1, name => 'foo1' }, {id => 10, parent => 0, level => 1, name => '****' }, {id => 9, parent => 10, level => 2, name => 'qwer' }, {id => 5, parent => 2, level => 3, name => 'lev3' }, {id => 7, parent => 5, level => 4, name => 'wxyz' }, ); my $tree = Build_Tree( \@list ); Print_Tree( $tree ); sub Build_Tree { my $list = shift; my %tree; for ( @$list ) { $tree{$_->{id}}{level} = $_->{level}; $tree{$_->{id}}{name} = $_->{name}; push @{ $tree{$_->{parent}}{children}} , $_->{id}; } return \%tree; } sub Print_Tree { my $tree = shift; my %seen; my @stack = sort { $b <=> $a } @{ $tree->{0}{children} }; while ( @stack ) { my $id = pop @stack; if ( $seen{$id} ) { print ' ' x (($tree->{$id}{level} - 1) * 5), "Circular det +ection\n"; next; } $seen{$id}++; print ' ' x (($tree->{$id}{level} - 1) * 5), $tree->{$id}{name +}, "\n"; push @stack , sort {$b <=> $a} @{$tree->{$id}{children}} if ex +ists $tree->{$id}{children}; } }
    Cheers - L~R


  • Comment on Re: Re: Re: group based array sort
    Download Code
    Re: Re: Re: Re: group based array sort
    by bageler (Hermit) on Feb 20, 2004 at 00:05 UTC
      thanks! I'll give them both a shot.

    Log In?
    Username:
    Password:

    What's my password?
    Create A New User
    Node Status?
    node history
    Node Type: note [id://330392]
    help
    Chatterbox?
    and the web crawler heard nothing...

    How do I use this? | Other CB clients
    Other Users?
    Others romping around the Monastery: (12)
    As of 2014-08-27 19:43 GMT
    Sections?
    Information?
    Find Nodes?
    Leftovers?
      Voting Booth?

      The best computer themed movie is:











      Results (250 votes), past polls