Re: number of unique characters in a string

Hi ,

The Hash can hold only unique keys and hence you can store the key as the split string .


      my $txt1 = "0101010101";
      my $count;
      my %hashofuniq;
      my @txt1 = split ('',$txt1);
      @hashofuniq{@txt1} = 1;
      foreach  (keys %hashofuniq){

        $count++; 

      }

      print "[$count]\n";
[download]

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

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Re: Re: number of unique characters in a string by rob_au (Abbot) on Mar 01, 2003 at 04:08 UTC
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"))'`	[reply] [d/l]
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]