power_of_two.cpp File Reference

Implementation to check whether a number is a power of 2 or not. More...

#include <iostream>

Include dependency graph for power_of_two.cpp:

Namespaces
namespace	math
	for std::rand

Functions
void	math::power_of_two (int n)
	Function to test above algorithm. More...
int	main ()
	Main function. More...

Detailed Description

Implementation to check whether a number is a power of 2 or not.

This algorithm uses bit manipulation to check if a number is a power of 2 or not.

Algorithm

Let the input number be n, then the bitwise and between n and n-1 will let us know whether the number is power of 2 or not

For Example, If N= 32 then N-1 is 31, if we perform bitwise and of these two numbers then the result will be zero, which indicates that it is the power of 2 If N=23 then N-1 is 22, if we perform bitwise and of these two numbers then the result will not be zero , which indicates that it is not the power of 2

Note

This implementation is better than naive recursive or iterative approach.

Author

Neha Hasija

Function Documentation

main()

int main

(

void

)

Main function.

Returns

0 on exit

n stores the input from the user

function call with

Parameters

n

           {
    int n = 0;
    /// n stores the input from the user
    std::cout << "enter a number " << std::endl;
    std::cin >> n;
    /// function call with @param n
    math::power_of_two(n);
    return 0;
}

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