# Set the K-th bit of a given number

Given a number n and a value k. From the right, set the kth bit in the binary representation of n. The position of LSB(or last bit) is 0, second last bit is 1 and so on. Also, 0 <= k < x, where x is the number of bits in the binary representation of n.

**Examples:**

Input : n = 10, k = 2 Output : 14(10)= (1010)_{10}_{2}Now, set the 2nd bit from right.(14)= (1_{10}110)_{2}2nd bit has been set. Input : n = 15, k = 3 Output : 15 3rd bit of 15 is already set.

To set any bit we use bitwise OR | operator. As we already know bitwise OR | operator evaluates each bit of the result to 1 if any of the operand’s corresponding bit is set (1). In-order to set kth bit of a number we need to shift 1 k times to its left and then perform bitwise OR operation with the number and result of left shift performed just before.

In general,(1 << k) | n.

## C++

`// C++ implementation to set the kth bit ` `// of the given number ` `#include <bits/stdc++.h> ` ` ` `using` `namespace` `std; ` ` ` `// function to set the kth bit ` `int` `setKthBit(` `int` `n, ` `int` `k) ` `{ ` ` ` `// kth bit of n is being set by this operation ` ` ` `return` `((1 << k) | n); ` `} ` ` ` `// Driver program to test above ` `int` `main() ` `{ ` ` ` `int` `n = 10, k = 2; ` ` ` `cout << ` `"Kth bit set number = "` ` ` `<< setKthBit(n, k); ` ` ` `return` `0; ` `} ` |

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## Java

`// Java implementation to set the kth bit ` `// of the given number ` ` ` `class` `GFG { ` ` ` `// function to set the kth bit ` `static` `int` `setKthBit(` `int` `n, ` `int` `k) ` `{ ` ` ` `// kth bit of n is being set by this operation ` ` ` `return` `((` `1` `<< k) | n); ` `} ` ` ` `// Driver code ` `public` `static` `void` `main(String arg[]) ` `{ ` ` ` `int` `n = ` `10` `, k = ` `2` `; ` ` ` `System.out.print(` `"Kth bit set number = "` `+ ` ` ` `setKthBit(n, k)); ` `} ` `} ` ` ` `// This code is contributed by Anant Agarwal. ` |

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## Python3

`# Python implementation ` `# to set the kth bit ` `# of the given number ` ` ` `# function to set ` `# the kth bit ` `def` `setKthBit(n,k): ` ` ` ` ` `# kth bit of n is being ` ` ` `# set by this operation ` ` ` `return` `((` `1` `<< k) | n) ` ` ` `# Driver code ` ` ` `n ` `=` `10` `k ` `=` `2` ` ` `print` `(` `"Kth bit set number = "` `, ` ` ` `setKthBit(n, k)) ` ` ` `# This code is contributed ` `# by Anant Agarwal. ` |

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## C#

`// C# implementation to set the ` `// kth bit of the given number ` `using` `System; ` ` ` `class` `GFG { ` ` ` `// function to set the kth bit ` `static` `int` `setKthBit(` `int` `n, ` `int` `k) ` `{ ` ` ` `// kth bit of n is being set ` ` ` `// by this operation ` ` ` `return` `((1 << k) | n); ` `} ` ` ` `// Driver code ` `public` `static` `void` `Main() ` `{ ` ` ` `int` `n = 10, k = 2; ` ` ` `Console.Write(` `"Kth bit set number = "` ` ` `+ setKthBit(n, k)); ` ` ` `} ` `} ` ` ` `// This code is contributed by ` `// Smitha Dinesh Semwal. ` |

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## PHP

`<?php ` `// PHP implementation to ` `// set the kth bit of ` `// the given number ` ` ` `// function to set ` `// the kth bit ` `function` `setKthBit(` `$n` `, ` `$k` `) ` `{ ` ` ` `// kth bit of n is being ` ` ` `// set by this operation ` ` ` `return` `((1 << ` `$k` `) | ` `$n` `); ` `} ` ` ` `// Driver Code ` `$n` `= 10; ` `$k` `= 2; ` `echo` `"Kth bit set number = "` `, ` ` ` `setKthBit(` `$n` `, ` `$k` `); ` ` ` `// This code is contributed by m_kit ` `?> ` |

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**Output:**

Kth bit set number = 14

This article is contributed by **Ayush Jauhari**. If you like GeeksforGeeks and would like to contribute, you can also write an article using contribute.geeksforgeeks.org or mail your article to contribute@geeksforgeeks.org. See your article appearing on the GeeksforGeeks main page and help other Geeks.

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