Re: Remove repeated characters from a string

Anonymous Monk,
The short answer is yes. The long answer is yes, but which simple line of code all depends on what you mean. That is why it is important not to leave ambiguity in your questions. It is frustrating to have people answer questions you did not ask.

Do you want to reduce only letters appearing twice that are together?
Do you want to reduce letters appearing twice that appear anywhere in the string?
Do you only want to perform the action if the letters appear exactly twice, but not greater than twice?

So as to not leave you with all questions and no answers. Take a look at this small snippet, it should help if what you are going for is option 3. It is intentionally "wordy" so that the process is more obvious.

#!/usr/bin/perl
use strict;
use warnings;

my $string = 'one bright day in the middle of the night';
my (%seen, $new_string);
for ( split // , $string ) {
    next if $seen{$_};
    $seen{$_}++;
    $new_string .= $_;
}
print "$new_string\n";
[download]

Cheers - L~R

Comment on Re: Remove repeated characters from a string Download Code

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Re:^2 Remove repeated characters from a string by Anonymous Monk on May 13, 2004 at 14:47 UTC
I wish to remove all repeating letters no matter where they are. I generating a key and can have no double letters at a max there can be 26 letters all unique	[reply]
Re:^3 Remove repeated characters from a string by Limbic~Region (Chancellor) on May 13, 2004 at 14:54 UTC
Anonymous Monk, Then it sounds like the code I provided is on the right track. It would need to be modified a bit to take into account your additional requirements. Again, this is why it is important to explain your problem without assuming things are just "understood". `#!/usr/bin/perl use strict; use warnings; my $string = 'One bright day in the middle of The Night'; my (%seen, $new_string); for my $char ( split // , $string ) { $char = lc $char; next if $seen{$char} \|\| $char !~ /^[a-z]$/; $seen{$char}++; $new_string .= $char; last if length $new_string == 26; } print "$new_string\n";` [download] I hope this helps - L~R	[reply] [d/l]
Re: Re:^2 Remove repeated characters from a string by CountZero (Bishop) on May 14, 2004 at 05:29 UTC
Interesting, ... Why is it that the key may not have repeating characters? CountZero "If you have four groups working on a compiler, you'll get a 4-pass compiler." - Conway's Law	[reply]