hash : how to add values and keys dynamically

ansh batra has asked for the wisdom of the Perl Monks concerning the following question:

hi monks
i have declared an hash now i want to add keys as well as values dynamically

if(this)
then add key

if(this)
then add value to a key

if(this)
then add another value the same key

in the end the hash may look something like this

  my %children = (
                  'a' => [ 'b', 'c' ],
                  'c' => [ 'x' ],
                  'b' => [ 'x' ],
                  'x' => [ 'y' ],
                  'y' => [ 'z' ],
                  'z' => [ ],
                  );
[download]

i am very bad with hashes.
please help

Comment on hash : how to add values and keys dynamically Download Code

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Re: hash : how to add values and keys dynamically by umasuresh (Hermit) on Dec 21, 2011 at 13:14 UTC
Here is an excellent perldoc tutorial to get started: HOH	[reply]
Re: hash : how to add values and keys dynamically by zwon (Abbot) on Dec 21, 2011 at 14:01 UTC
Not sure what do you want but maybe this will help: `my %hash; for (qw(a b c)) { push @{ $hash{key} }, $_ if 'this'; }` [download]	[reply] [d/l]
Re: hash : how to add values and keys dynamically by Anonymous Monk on Dec 21, 2011 at 15:04 UTC
It might well be much simpler than you think. Perl has a very cool feature that is known by the fancy-pants term, “auto-vivication,” which basically means that you can create complicated data structures “all at once,” automagically creating the intervening hashes, hash-slots and so on without having to do so pedantically. You can also do things in one step, e.g. `$$myhash{'foo'}++;` will automagically create a `'foo'` slot, with an initial value of zero (subsequently incremented to 1 as you requested), and “It Just Works.™” Perl is very much a pragmatic language, built by real-world practitioners (not academics) to earn their daily bread.	[reply]