?
Solved

swapping two variables without a temp variable

Posted on 2001-06-08
4
Medium Priority
?
241 Views
Last Modified: 2010-04-02
suggest code in C to swap two variables without using a temporary variable. preferably a single statement.
0
Comment
Question by:falkon
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 2
4 Comments
 
LVL 5

Accepted Solution

by:
proskig earned 150 total points
ID: 6166959
 b ^= a;
  a ^= b;
  b ^= a;

b and a will be swapped


Note also that it is C++ area
0
 
LVL 1

Expert Comment

by:harrlow
ID: 6173264
Using C..

a = a + b;
b = a - b;
a = a - b;
0
 
LVL 5

Expert Comment

by:proskig
ID: 6176416
The obvious problem with harrlow's code is that it does not work in general case due to size limit (just suppose that a and b are int's and they are close to INT_MAX)
0
 

Expert Comment

by:EliezerGarza
ID: 7590358
but you can use:
   a=a-b
   b=a+b
   a=b-a
instead of:
   a=a+b
   b=a-b
   a=a-b
or for extra CPU usage:
   a=a*b
   b=a/b
   a=a/b
or any other of many ways. This is just an academical question, so the important thing is not if it works 100% of the cases or not, but how would you do it.

0

Featured Post

VIDEO: THE CONCERTO CLOUD FOR HEALTHCARE

Modern healthcare requires a modern cloud. View this brief video to understand how the Concerto Cloud for Healthcare can help your organization.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Article by: SunnyDark
This article's goal is to present you with an easy to use XML wrapper for C++ and also present some interesting techniques that you might use with MS C++. The reason I built this class is to ease the pain of using XML files with C++, since there is…
Often, when implementing a feature, you won't know how certain events should be handled at the point where they occur and you'd rather defer to the user of your function or class. For example, a XML parser will extract a tag from the source code, wh…
The goal of the video will be to teach the user the difference and consequence of passing data by value vs passing data by reference in C++. An example of passing data by value as well as an example of passing data by reference will be be given. Bot…
The viewer will learn how to clear a vector as well as how to detect empty vectors in C++.
Suggested Courses

762 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question