Skip to main content

Simple Problem in C++

Interchanging the values of two variables…

What’s the big deal. You take one extra variable; put the first variable’s value in it, copy the value of the second variable to the first one and then copy the value of the extra variable to the first one and there you are! But what, if I say that you don’t have to use the third variable, let’s say because the memory is full and you are left with memory only sufficient for storing two variables. Doesn’t make sense. Huh! It makes sense if you want to gain programming skills because solving problems is the only way to do it. In this article we start with a simple one.

So, how do we do it?

It is not very big deal to interchange the values of two variables without using the third variable yet I have come across peoples who don’t think it can be done. To solve this problem we need to do two things (i)First we need to write down the method (algorithm) of doing it (ii0 Secondly, we need to write the c++ code from the algorithm.

The Method

The method of solving this problem is discussed in a step-by-step manner to make it easily understandable.

SETP 1: Let us assume that we have two variables. First variable is named var1 and second var2.

STEP 2: WE put different values int the variables. Suppose we put the following values. var1=15 var2=5

STEP 3: We have to do the following addition and subtraction var1=var1-var2 (Now var1=10)

var2=var1+var2 (Now var2=15)

var1=var2-var1 (Now var1=5)

STEP 4: Wow! The values of the variable have been interchanged. Initially the values were var1=15; var2=5 And now they are var1=5; var2=15

Now we proceed to the second part…

Program it

All said and done; now we only need to program it.

   //Program to interchange the values of
   //two variables without using the third one
   #include<iostream.h>
   void main(void)
   {
   int var1,var2;
   cout<<"Enter two numbers:";
   cin>>var1>>var2;
   //intercahnge is done here
   var1=var1-var2;
   var2=var1+var2;
   var1=var2-var1;
   cout<<endl<<"After interchange values are:";
   cout<<endl<<var1<<endl<<var2<<endl;
   }

Simple isn’t it, how about trying this with three variables, for instance if the initial values three variables are a=5; b=15; c=25 then after interchange the values should be a=15; b=25; c=5. Go ahead its easy!

Related Articles:

Popular posts from this blog

Fix For Toshiba Satellite "RTC Battery is Low" Error (with Pictures)

RTC Battery is Low Error on a Toshiba Satellite laptop "RTC Battery is Low..." An error message flashing while you try to boot your laptop is enough to panic many people. But worry not! "RTC Battery" stands for Real-Time Clock battery which almost all laptops and PCs have on their motherboard to power the clock and sometimes to also keep the CMOS settings from getting erased while the system is switched off.  It is not uncommon for these batteries to last for years before requiring a replacement as the clock consumes very less power. And contrary to what some people tell you - they are not rechargeable or getting charged while your computer or laptop is running. In this article, we'll learn everything about RTC batteries and how to fix the error on your Toshiba Satellite laptop. What is an RTC Battery? RTC or CMOS batteries are small coin-shaped lithium batteries with a 3-volts output. Most laptops use

The Best Way(s) to Comment out PHP/HTML Code

PHP supports various styles of comments. Please check the following example: <?php // Single line comment code (); # Single line Comment code2 (); /* Multi Line comment code(); The code inside doesn't run */ // /* This doesn NOT start a multi-line comment block /* Multi line comment block The following line still ends the multi-line comment block //*/ The " # " comment style, though, is rarely used. Do note, in the example, that anything (even a multi-block comment /* ) after a " // " or " # " is a comment, and /* */ around any single-line comment overrides it. This information will come in handy when we learn about some neat tricks next. Comment out PHP Code Blocks Check the following code <?php //* Toggle line if ( 1 ) {      // } else {      // } //*/ //* Toggle line if ( 2 ) {      // } else {      // } //*/ Now see how easy it is to toggle a part of PHP code by just removing or adding a single " / " from th

Designing a Simple Order Form Application in PHP

Ok guys, for this post we’re going to create a simple yet complete order form page. Order forms are used on many sites to take customers order online. Order forms should have the capability to take orders from visitors regarding what items they want to purchase and store the information for further processing. For this post’s example, we are going to create an order form for a Book Seller. The form will be designed to take order of five different items (books). Our order form application should be able to take order of five different items in any separate quantities tht user wants, it should also ask for shipping address and name of the customer. It should then store the information provided in a file along with the date and time order was placed. The application should also be able to take any number of orders and store them all linearly for further human processing. For this, we need a front end of a HTML form to which the user would interact a