[id://spurperl] is right, table lookup is fastest. Using the notation op for [id://PerlingTheUK|original poster], lt for "lookup table", and the rest obvious, the overall benchmark looks something like this:

         Rate  op4  op5  hv7  hv6 roy4 kaif   lt
op4   64233/s   -- -33% -33% -52% -57% -72% -76%
op5   96098/s  50%   --  -0% -28% -36% -58% -64%
hv7   96399/s  50%   0%   -- -28% -35% -58% -64%
hv6  134032/s 109%  39%  39%   -- -10% -41% -50%
roy4 149447/s 133%  56%  55%  12%   -- -34% -45%
kaif 227019/s 253% 136% 135%  69%  52%   -- -16%
lt   270514/s 321% 181% 181% 102%  81%  19%   --

[download]

Just be sure to initialize your table outside of your function, that is, initialize only once.

In reply to Re^2: Loops loosing Performance by kaif
in thread Loops loosing Performance by PerlingTheUK

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.