In languages like C (and not Perl) where it sometimes makes sense to use this method for swapping values, it will work just fine even if the values are the same. I'm unsure what you mean by "overlap." To see that it will work, try it with all four combinations of 2 bits:
A | B | A = A^B | B = A^B | A = A^B | A | B
===|===|=========|=========|=========|===|===
0 | 0 | 0 = 0^0 | 0 = 0^0 | 0 = 0^0 | 0 | 0
---+---+---------+---------+---------+---+---
0 | 1 | 1 = 0^1 | 0 = 1^1 | 1 = 1^0 | 1 | 0
---+---+---------+---------+---------+---+---
1 | 0 | 1 = 1^0 | 1 = 1^0 | 0 = 1^1 | 0 | 1
---+---+---------+---------+---------+---+---
1 | 1 | 0 = 1^1 | 1 = 0^1 | 1 = 0^1 | 1 | 1
See? It works fine even when the values are equal.
But, don't do it in perl!
-sauoq
"My two cents aren't worth a dime.";
-
Are you posting in the right place? Check out Where do I post X? to know for sure.
-
Posts may use any of the Perl Monks Approved HTML tags. Currently these include the following:
<code> <a> <b> <big>
<blockquote> <br /> <dd>
<dl> <dt> <em> <font>
<h1> <h2> <h3> <h4>
<h5> <h6> <hr /> <i>
<li> <nbsp> <ol> <p>
<small> <strike> <strong>
<sub> <sup> <table>
<td> <th> <tr> <tt>
<u> <ul>
-
Snippets of code should be wrapped in
<code> tags not
<pre> tags. In fact, <pre>
tags should generally be avoided. If they must
be used, extreme care should be
taken to ensure that their contents do not
have long lines (<70 chars), in order to prevent
horizontal scrolling (and possible janitor
intervention).
-
Want more info? How to link
or How to display code and escape characters
are good places to start.
|
