#!/usr/bin/perl -w
use strict;
my @words = qw(foo bar);
my @lines = ("foo before bar\n",
         "the word is foo\n",
         "one goes over the mountain\n",
         "one reaches the bar\n",
         "Here foo is in the middle\n",
         "foo on you\n",
             "this foobar will be regected\n");
my $istrue = 0;
my $line;
my $word;
foreach $line (@lines) {
    $istrue = 0;
    foreach $word (@words) {
        if ($line =~ /\b$word\b/) {
            $istrue = 1;
        } 
    }
    if ($istrue) {
        print $line;
    }
}
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