Toggling k-th bit of a number

For a given number n, if k-th bit is 0, then toggle it to 1 and if it is 1 then, toggle it to 0.

Examples :

Input : n = 5, k = 1
Output : 4
5 is represented as 101 in binary
and has its first bit 1, so toggling 
it will result in 100 i.e. 4.

Input : n = 2, k = 3
Output : 6

Input : n = 75, k = 4
Output : 67

Below are simple steps to find value of k-th bit

1) Left shift given number 1 by k-1 to create 
   a number that has only set bit as k-th bit.
    temp = 1 << (k-1)
2) Return bitwise XOR of temp and n.  Since temp
   has only k-th bit set, doing XOR would toggle 
   only this bit.

Example :

 n = 75 and k = 4
 temp = 1 << (k-1) = 1 << 3 = 8 
 Binary Representation of temp = 0..00001000 
 Binary Representation of n = 0..01001011 
 Bitwise XOR of two numbers = 0..01000011

C++

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// CPP program to toggle k-th bit of n
#include<iostream>
using namespace std;
  
int toggleKthBit(int n, int k)
{
    return (n ^ (1 << (k-1)));
}
  
// Driver code
int main()
{
    int n = 5, k = 1;
    cout << toggleKthBit(n , k);
    return 0;
}

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Java

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// Java program to toogle
// k-th bit of a number
  
class Toggle
{
    static int toggleKthBit(int n, int k)
    {
        return (n ^ (1 << (k-1)));
    }
      
    // main function 
    public static void main (String[] args) 
    {   
        int n = 5, k = 1;
        System.out.println(toggleKthBit(n , k));
    }
}

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Python3

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# Python3 code to toggle k-th bit of n
  
def toggleKthBit(n, k):
    return (n ^ (1 << (k-1)))
      
# Driver code
n = 5
k = 1
print( toggleKthBit(n , k))
  
# This code is contributed by "Sharad_Bhardwaj".

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C#

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// C# program to toogle
// k-th bit of a number
using System;
  
class GFG {
      
    static int toggleKthBit(int n, int k)
    {
        return (n ^ (1 << (k-1)));
    }
       
    // main function 
    public static void Main() 
    {   
        int n = 5, k = 1;
          
        Console.WriteLine(toggleKthBit(n , k));
    }
}
  
//This code is contributed by Anant Agarwal.

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PHP

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<?php
// Php program to toggle k-th bit of n
  
function toggleKthBit($n, $k)
{
    return ($n ^ (1 << ($k - 1)));
}
  
// Driver code
$n = 5;
$k = 1;
echo toggleKthBit($n, $k);
  
// This code is contributed by Ajit
?>

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Output :



4

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Improved By : jit_t

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