You have a hash with two name/value pairs. 
$var1 = "2000";
$var2 = "02";
$var3 = "2000";
$var4 = "2";

$var2 does not get interpolated - ie, "02" is not the same as "2" in t
+he context you used. To force numerical context:

$array{$var2} = $array{"02"} = undefined 
$array{$var2+0} = $array{"2"} = 125

[download]
1 and 2 are the only KEYS in the hash, so others are undefined. And I would rename %array to %hash to avoid confusion with this.

I suggest you read perldata document to familiarise yourself with Perl's data structures.

cLive ;-)

Update: - oops, misread (thanks Sifmole) - have amended above to explain.

In reply to Re: Number notation by cLive ;-)
in thread Number notation by Michalis

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.