my @fhs = map { open my $FH, '<', $_ or die $!; $FH } @filenames;
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($q=q:Sq=~/;[c](.)(.)/;chr(-||-|5+lengthSq)`"S|oS2"`map{chr |+ord
}map{substrSq`S_+|`|}3E|-|`7**2-3:)=~y+S|`+$1,++print+eval$q,q,a,
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Did you try it? And what went wrong?

yes, I tried it this way:

#! /usr/bin/perl

use strict;
use warnings;
use IO::File;


my @fh;
my @file_names = ("output1.txt", "output2.txt", "output3.txt");

while ( <> ){
    for (my $i=0; $i<=$#file_names; $i++){
        $fh[$i]= IO::File->new( ">$file_names[$i]" ) || die "Cannot op
+en $file_names[$i]: $!.\n";
        print {$fh[$i]} "$_";
    }
}
print "done.\n";
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this script produces three output files, each contains the input filename that the user writes into the command line. Do I have to somehow open the input files in the script?

Do I have to somehow open the input files in the script?

Yes.

open my $input_file, '<', $input_filename or die "Cannot open input fi
+le $input_filename:  $!.\n";
while (my $input_line = <$input_file>) {
    chomp $input_line;
    print "[$input_line]\n";
}
close $input_file;
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