please put your code between <code> </code> tags, like this
my %hash=(inst => { dept1 => { rollno=> { [name,marks], [name1,marks1] +, }, inst2.... });


do you want to sort by inst, dept, marks?
I think we need a little more description of your structure, rollno is that a constant, or is it a value like isnt or dept1? why are the marks in array refs inside a hashref, which wouldn't work if you had an odd number of names. You would want them either in an arrayref like rollno => [ [name, marks], ... ] or in a hashref like rollno => { name => marks, name => marks, ... }.

And as mentioned in another response, supply what your data would look like sorted.

In reply to Re: sorting in hashes by james2vegas
in thread sorting in hashes by Anonymous Monk

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.