Perl: How to check if values in file 2 are in file 1? [RESOLVED]

[TDQWERTY]

Hi, during some tests, i found that file comparing, line by line is slow, probably i didn't do it right too.
So what i'm looking for are best ways to do that.
I wanted to check if values from file2.txt are in file1.txt and if they exist (Ignore case), report to stdout.

open( WORDS1, "words01.txt");
open( WORDS2, "words02.txt");
@allwords1=<WORDS1>;
@allwords2=<WORDS2>;
foreach(@allwords1){
 chomp($myword=$_);
 foreach(@allwords2){
  chomp($myword2=$_);
  if($myword1 =~ /$myword2/i){
   print $myword1, "was found on both files!\n";
  }
 }
}

EDIT: Resolved.