arrays and strings

Anonymous Monk has asked for the wisdom of the Perl Monks concerning the following question:

I am simply concatenating strings together based on numbers in an array (see below). However, i'm struggling to adapt the code to take into consideration a third array (@check) which holds consecutive numbers with increments of 1.

e.g.

my @numbers = ('1', '2', '2', '3', '3');
my @strings = ('hello', 'green', 'grass', 'rainbow', 'pretty');
my @new_strings;
[download]

So the output is:

hello
greengrass
rainbowpretty
[download]

Heres the code to do this:

for ( 0 .. $#numbers ) {
  push @{$h{$numbers[$_]}}, $strings[$_];
}
for ( sort { $a <=> $b } keys %h ) {
  push @new_strings, join('', @{$h{$_}}), ">>\n";
}
                                                                      
+                                      
my $v = join ('', @new_strings);
@new_strings = split (/>>/, $v);                                      
+                                                                     
+                                  
my @final_strings;
                                                                      
+                                                                     
+  
for (my $k=0; $k<@new_strings; $k++)     {
             $new_strings[$k] =~ s/\n+//g;
             $new_strings[$k] =~ s/\s+//g;

              if ($new_strings[$k] =~ /\w+/)   {
                       push @final_strings, "$new_strings[$k]";
              }
}
[download]

## PROBLEM ! ==================== If @check contains a number not present in @numbers, I want 'xxxxxxxx' to be inserted into the output in its place. I hope someone can help! #\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\

@check = ('1','2','3','4');

# desired output:
#-----------------
hello
greengrass
rainbowpretty
xxxxxxxx       # THE 4TH ELEMENT NOW CONTAINS 'xxxxxxxx' as there isn'
+t a '4' in @numbers
[download]

Comment on arrays and strings Select or Download Code

Replies are listed 'Best First'.
Re: arrays and strings by ccn (Vicar) on Aug 31, 2004 at 14:06 UTC
`my @numbers = (1, 2, 2, 3, 3); my @strings = qw(hello green grass rainbow pretty); my @check = (1, 2, 3, 4); my @new_strings; foreach (@numbers) { die "string $_ does not exists" unless defined $strings[$_-1]; $new_strings[$_-1] .= $strings[$_-1]; } foreach (@check) { $new_strings[$_-1] = 'xxxxxx' unless defined $new_strings[$_-1]; } print $_, "\n" for grep defined, @new_strings;` [download] Update: filtered output, indexes corrected	[reply] [d/l]
Re^2: arrays and strings by Anonymous Monk on Aug 31, 2004 at 14:20 UTC
hi ccn! thanks for your help, but i can't get this to work right. my outputm from it is: `green grassgrass rainbowrainbow xxxxxx green grassgrass rainbowrainbow xxxxxx green grassgrass rainbowrainbow xxxxxx green grassgrass rainbowrainbow xxxxxx` [download] I need: `hello greengrass rainbowpretty xxxxxxxx # where @numbers basically refers to which line the strings should be +printed to` [download]	[reply] [d/l] [select]
Re: arrays and strings by Gunth (Scribe) on Aug 31, 2004 at 15:25 UTC
Probably broken, but something to work off of I suppose `#!/usr/bin/perl use strict; use warnings; my @numbers = (1, 2, 2, 3, 3); my @strings = qw(hello green grass rainbow pretty); my @check = (1, 2, 3, 4); my @con; for (0 .. $#numbers) { push @{$con[$numbers[$_]]}, $strings[$_]; } for (@check) { if ($con[$_]) { print @{$con[$_]}; } else { print 'xxxxxxxxx'; } print "\n"; } __DATA__ hello greengrass rainbowpretty xxxxxxxxx` [download] -Will	[reply] [d/l]
Re: arrays and strings by revdiablo (Prior) on Aug 31, 2004 at 17:12 UTC
Here's how I'd approach it: `my @numbers = qw(1 2 2 3 3); my @strings = qw(hello green grass rainbow pretty); my @check = qw(1 2 3 4); my %concat; for (0 .. $#numbers) { $concat{$numbers[$_]} .= $strings[$_]; } for (@check) { print $concat{$_} \|\| "xxxxxxxx", "\n"; }` [download]	[reply] [d/l]