Any time you want to know if one value is in a set of others, you probably want a hash. Convert @b to a hash (with the values as keys), then loop on @a, checking if the values exist in %b. Here's an example:

    my @a = qw(one two three four);
    my @b = qw(two four);
    my %b;
    @b{ @b } = (1)x@b; # one of many ways to create the hash

    for (@a) {
      unless ($b{$_}) { print "$_ is not in \@b\n" }
    }

[download]

In reply to Re: Need to Create an Array of Differences by revdiablo
in thread Need to Create an Array of Differences by scottj

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.