Re: Re: number of unique characters in a string

You're on the right track, but I think this could be made more perl-ish again ...

my $text = '0101010101';
my %hash;
@hash{ split '', $text } = 1;
print scalar keys %hash, "\n";
[download]

perl -le 'print+unpack("N",pack("B32","00000000000000000000001000110111"))'

Comment on Re: Re: number of unique characters in a string Download Code

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Hash syntax tidbit by crenz (Priest) on Mar 01, 2003 at 17:54 UTC
++ for teaching me a new hash syntax tidbit: I never knew about the @hash{@list_of_keys} = @list_of_values; syntax. Thanks!	[reply]
Re: Re: Re: number of unique characters in a string by genecutl (Beadle) on Mar 03, 2003 at 23:41 UTC
`my $text = '0101010101'; my %hash; @hash{ split '', $text } = 1; print scalar keys %hash, "\n";` [download] Although this code above will work correctly, it will not be doing so the way that you expected which could lead you to trouble. `@hash{@array} = $scalar` [download] only sets $scalar as the value for the first key in %hash. To set all the keys, you'd want to do something like: `@hash{@array} = ($scalar) x scalar @array;` [download] In the actual code above, since you don't check values anyway, you can just write: `@hash{@array} = ();` [download]	[reply] [d/l] [select]