# 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)10 = (1010)2
Now, set the 2nd bit from right.
(14)10 = (1110)2
2nd bit has been set.

Input : n = 15, k = 3
Output : 15
3rd bit of 15 is already set.
```

## Recommended: Please solve it on “PRACTICE” first, before moving on to the solution.

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 ` ` `  `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; ` `}  `

## 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. `

## 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. `

## 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. `

## PHP

 ` `

Output:

```Kth bit set number = 14
```

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