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4 Different methods to swap 2 numbers

Swapping 2 numbers is one of the favorite questions asked to a lot of people during their interviews. There are a lot of ways to swap 2 numbers. In this post we have 4 methods that can be used to swap 2 numbers.

First Method : Using addition and subtraction method
This method is a simple method that can be used to swap 2 numbers, the method can be used for all integer, float and double variables. The method involves one addition and two subtraction operations.

Second Method : Using multiplication and division operators
This method is simply obtained by replacing + by * and - by / operator in the above method, but this method cannot be used when one of the numbers is 0 as it involves division operation.

Third Method : Using the EX-OR operation
This method involves repeated ex-or operations between 2 numbers to swap 2 numbers. But this method can be used only for integers and cannot be used for float or double variables as bit operations for them are not defined.

Fourth Method : Using temp Variable
This is the simplest and the most common method used by a lot of people.

The Following is full C implementation of the above described methods.

C Program

Sample input and output to check the program


Different methods to swap 2 numbers

You might also be interested in 

Bubble Sort
Insertion Sort
Selection sort
Shell Sort
Hashing with Linear Probing
Hashing with Quadratic Probing
Double Hashing


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