Here is the code with the change
use strict;
use warnings;

open( my $fh, '<', 'input.txt') or die "Error opening file - $!\n";
open OUT, ">", "output.txt" or die "could not open output.txt $! \n";

my $this_line = "";
my $do_next = 0;
my $data = <DATA>;

while(<$fh>) {
    my $last_line = $this_line;
    $this_line = $_;
    
    chomp $data;
    if ($this_line =~ /\Q$data/) {
        print OUT $last_line unless $do_next;
        print OUT $this_line;
        $do_next = 1;
    } else {
        print OUT $this_line if $do_next;
        $last_line = "";
        $do_next = 0;
    }
}
close ($fh);

__DATA__
4386_7#8
4350_7#6
4414_1#6

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In reply to Re^6: How to print the lines immediately above and below a matching line? by Bio90
in thread How to print the lines immediately above and below a matching line? by Bio90

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