undef $/;
my @text = split (//, <$FILE>);
for (my $i = 0; $i <= $#text; $i++) {
    my $j = $i;
    if (($text[$i++] == 'h' || $text[$i++] == 'H') && 
        $text[$i++] == 'e'...) {
        while ($j <= $i) {
            print $text[$j++];            
        }
    }    
}