Re^4: Print to specific line

I agree with Laurent. Using both is unnecessary.

Here's an adjusted version which only uses a hash and accounts for possible missing line numbers, which prevents the uninitialized warnings.

use 5.010;
use strict;
use warnings;
use List::Util qw( max );

my %hash = (
  4 => 'The future is unknown.',
  1 => 'The day before yesterday sucked.',
  5 => 'Today is a good day.',
  3 => 'Not much hope for tomorrow.',
);

my $last = max keys %hash;

for my $line ( 1 .. $last ) {
    say exists $hash{$line} ? $hash{$line} : '';
}
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Comment on Re^4: Print to specific line Download Code

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Re^5: Print to specific line by GotToBTru (Prior) on Jun 23, 2015 at 19:01 UTC
If, as I suspect, the OP does not want the numbers to print: `use strict; use warnings; my (%hash); while (<>) { chomp; my ($text,$line) = $_ =~ m/(.+)(\d+)$/; $hash{$line} = $text; } print $hash{$_} . "\n" for (sort keys %hash)` [download] Since I use only the keys, no worries about missing line numbers. Usage: `perl pm1.pl < input.txt > output.txt` [download] Update: I along with other respondents missed the fact that there could potentially be non-sequential line numbers in the data, and there might need to be blank lines created accordingly. Updated again to be a bit more perlish. `use strict; use warnings; my (@array); while (<>) { $array[$2] = 1 if ($_ =~ m/(.+)(\d+)$/) } print defined $_ ? $_ . "\n" : "\n" for @array[1..$#array];` [download] Dum Spiro Spero	[reply] [d/l] [select]

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Re^5: Print to specific line
by GotToBTru (Prior) on Jun 23, 2015 at 19:01 UTC

If, as I suspect, the OP does not want the numbers to print:

use strict;
use warnings;
my (%hash);
while (<>) {
  chomp;
  my ($text,$line) = $_ =~ m/(.+)(\d+)$/;
  $hash{$line} = $text;
}
print $hash{$_} . "\n" for (sort keys %hash)
[download]

Since I use only the keys, no worries about missing line numbers.

Usage:

perl pm1.pl < input.txt > output.txt
[download]

Update: I along with other respondents missed the fact that there could potentially be non-sequential line numbers in the data, and there might need to be blank lines created accordingly. Updated again to be a bit more perlish.

use strict;
use warnings;
my (@array);
while (<>) {
  $array[$2] = 1 if ($_ =~ m/(.+)(\d+)$/)
}
print defined $_ ? $_ . "\n" : "\n" for @array[1..$#array];
[download]

Dum Spiro Spero

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