# Multiply any Number with 4 using Bitwise Operator

Last Updated : 25 Nov, 2022

We are a Number n and our task is to multiply the number by 4 using a bit-wise Operator.

Examples:

```Input : 4
Output :16

Input :5
Output :20```

Explanation Case 1:- n=4 the binary of 4 is 100 and now shifts two bit right then 10000 now the number is 16 is multiplied 4*4=16 ans.
Approach :- (n<<2) shift two bit right

## C++

 `// C++ program to multiply a number with ` `// 4 using Bitwise Operator` `#include ` `using` `namespace` `std;`   `// function the return multiply a number` `//  with 4 using bitwise operator` `int` `multiplyWith4(``int` `n)` `{` `    ``// returning a number with multiply ` `    ``// with 4 using2 bit shifting right` `    ``return` `(n << 2);` `}`   `// derive function` `int` `main()` `{` `    ``int` `n = 4;` `    ``cout << multiplyWith4(n) << endl;` `    ``return` `0;` `}`

## Java

 `// Java program to multiply a number` `// with 4 using Bitwise Operator`   `class` `GFG {` `    `  `// function the return` `// multiply a number` `// with 4 using bitwise ` `// operator` `static` `int` `multiplyWith4(``int` `n)` `{` `    `  `    ``// returning a number` `    ``// with multiply with ` `    ``// 4 using 2 bit shifting` `    ``// right` `    ``return` `(n << ``2``);` `}`   `// Driver Code` `public` `static` `void` `main(String[] args)` `{` `    ``int` `n = ``4``;` `    ``System.out.print(multiplyWith4(n));` `}` `}`   `// This code is contributed by Smitha.`

## Python 3

 `# Python 3 program to multiply` `# a number with 4 using Bitwise` `# Operator`   `# function the return multiply` `# a number with 4 using bitwise` `# operator` `def` `multiplyWith4(n):`   `    ``# returning a number with` `    ``# multiply with 4 using2` `    ``# bit shifting right` `    ``return` `(n << ``2``)`   `# derive function` `n ``=` `4` `print``(multiplyWith4(n))`   `# This code is contributed` `# by Smitha`

## C#

 `// C# program to multiply a number` `// with 4 using Bitwise Operator` `using` `System;`   `class` `GFG {` `    `  `// function the return` `// multiply a number` `// with 4 using bitwise ` `// operator` `static` `int` `multiplyWith4(``int` `n)` `{` `    `  `    ``// returning a number` `    ``// with multiply with ` `    ``// 4 using 2 bit shifting` `    ``// right` `    ``return` `(n << 2);` `}`   `// Driver Code` `public` `static` `void` `Main(String[] args)` `{` `    ``int` `n = 4;` `    ``Console.Write(multiplyWith4(n));` `}` `}`   `// This code is contributed by Smitha.`

## PHP

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## Javascript

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Output

```16
```

Time Complexity: O(1)
Auxiliary Space: O(1)

Generalization : In general, we can multiply with a power of 2 using bitwise operators. For example, suppose we wish to multiply with 16 (which is 24), we can do it by left shifting by 4.

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