set_kth_bit.cpp File Reference

Implementation to [From the right, set the Kth bit in the binary representation of N] (https://practice.geeksforgeeks.org/problems/set-kth-bit3724/1/) in an integer. More...

#include <cassert>
#include <cstdint>
#include <iostream>

Include dependency graph for set_kth_bit.cpp:

Go to the source code of this file.

Namespaces
namespace	bit_manipulation
	for assert
namespace	setKthBit
	Functions for the [From the right, set the Kth bit in the binary representation of N] (https://practice.geeksforgeeks.org/problems/set-kth-bit3724/1/) implementation.

Functions
std::uint64_t	bit_manipulation::set_kth_bit::setKthBit (std ::int64_t N, std ::int64_t k)
	The main function implements set kth bit.
static void	test ()
	Self-test implementations.
int	main ()
	Main function.

Detailed Description

Implementation to [From the right, set the Kth bit in the binary representation of N] (https://practice.geeksforgeeks.org/problems/set-kth-bit3724/1/) in an integer.

Given a number N and a value K. From the right, set the Kth bit in the binary representation of N. The position of Least Significant Bit(or last bit) is 0, the second last bit is 1 and so on. in it.

A binary number consists of two digits. They are 0 & 1. Digit 1 is known as set bit in computer terms. Worst Case Time Complexity: O(1) Space complexity: O(1)

Author

Aman Raj

Definition in file set_kth_bit.cpp.

Function Documentation

main()

int main

(

void

)

Main function.

Returns

0 on exit

Definition at line 77 of file set_kth_bit.cpp.

           {
    test();  // run self-test implementations
    return 0;
}

setKthBit()

std::uint64_t bit_manipulation::set_kth_bit::setKthBit	(	std ::int64_t	N,
		std ::int64_t	k )

The main function implements set kth bit.

Parameters

N	is the number whose kth bit will be set

Returns

returns an integer after setting the K'th bit in N

Definition at line 43 of file set_kth_bit.cpp.

                                       {  // int64_t is preferred over int so
                                            // that no Overflow can be there.
 
    int pos =
        1 << k;  // "pos" variable is used to store 1 at kth postion and
                 // rest bits are 0. in binary representation of number 'n'
 
    return N | pos;  // by taking or with the pos and the N we set the bit of N
                     // at kth position.
}

test()

static void test ( )

static

Self-test implementations.

Returns

void

Definition at line 61 of file set_kth_bit.cpp.

                   {
    // n = 10,2 return 14
    assert(bit_manipulation::set_kth_bit::setKthBit(10, 2) == 14);
    // n = 25,1 return 27
    assert(bit_manipulation::set_kth_bit::setKthBit(25, 1) == 27);
    // n = 400001,5 return 400033
    assert(bit_manipulation::set_kth_bit::setKthBit(400001, 5) == 400033);
    // n = 123 return 123
    assert(bit_manipulation::set_kth_bit::setKthBit(123, 3) == 123);
 
    std::cout << "All test cases successfully passed!" << std::endl;
}