I'm iterating through an array of arrayrefs and find that the value of $#{$eventscores} changes at the end of the inner while loop (I've printed it out to check). Here is my code 
# $eventscores is an arrayref to an array of arrayrefs.
# everything works fine until the last while iteration
while ( $i <= $#{$eventscores} ) {
        $rider_id = $eventscores->[$i]->[0];
        while ( $eventscores->[$i]->[0] == $rider_id ){
            push (@scores, $eventscores->[$i]->[2] );
            $i++;
        }
#...more code.. unrelated to loop
}

[download]
This will go into an endless loop because the value of $#{$eventscores) changes when the value of $i is incremented beyond it (where it should end) Here is the key dilemma for me. If I assign 
$array_count = $#{$eventscores}

[download]
then set up the loop as 
while ($i <= $array_count)

[download]
it works. Why? Thanks

In reply to $#{$array_ref} changes in loop by thomc

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.