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# Check whether a given number is even or odd

• Difficulty Level : Basic
• Last Updated : 25 Mar, 2021

Given a number, check whether it is even or odd. Examples :

```Input: 2
Output: even

Input: 5
Output: odd```

One simple solution is to find the remainder after dividing by 2.

## C++

 `// A simple C++ program to``// check for even or odd``#include ``using` `namespace` `std;` `// Returns true if n is``// even, else odd``bool` `isEven(``int` `n) { ``return` `(n % 2 == 0); }` `// Driver code``int` `main()``{``    ``int` `n = 101;``    ``isEven(n) ? cout << ``"Even"` `: cout << ``"Odd"``;` `    ``return` `0;``}`

## Java

 `// Java program program to``// check for even or odd` `class` `GFG``{``    ``// Returns true if n is even, else odd``    ``public` `static` `boolean` `isEven(``int` `n)``    ``{``        ``return` `(n % ``2` `== ``0``);``    ``}``    ` `    ``// Driver code``    ``public` `static` `void` `main(String[] args)``    ``{``        ``int` `n = ``101``;``        ``if``(isEven(n) == ``true``)``            ``System.out.print(``"Even"``);``        ``else``            ``System.out.print(``"Odd"``);``    ``}``}` `// This code is contributed by rishabh_jain`

## Python3

 `# A simple Python3 code``# to check for even or odd` `# Returns true if n is even, else odd``def` `isEven(n):``    ``return` `(n ``%` `2` `=``=` `0``)``    ` `# Driver code``n ``=` `101``print``(``"Even"` `if` `isEven(n) ``else` `"Odd"``)` `# This code is contributed by "Sharad_Bhardwaj".`

## C#

 `// C# program program to``// check for even or odd``using` `System;` `class` `GFG``{``    ``// Returns true if n is even, else odd``    ``public` `static` `bool` `isEven(``int` `n)``    ``{``        ``return` `(n % 2 == 0);``    ``}``    ` `    ``// Driver code``    ``public` `static` `void` `Main()``    ``{``        ``int` `n = 101;``        ``if``(isEven(n) == ``true``)``            ``Console.WriteLine(``"Even"``);``        ``else``            ``Console.WriteLine(``"Odd"``);``    ``}``}` `// This code is contributed by vt_m`

## PHP

 ``

## Javascript

 ``

Output :

`Odd`

Time Complexity: O(1)

Auxiliary Space: O(1)
A better solution is to use bitwise operators. We need to check whether last bit is 1 or not. If last bit is 1 then number is odd, otherwise always even.
Explanation:

``` input : 5    // odd
00000101
& 00000001
--------------
00000001
--------------

input : 8     //even
00001000
& 00000001
--------------
00000000
--------------```

Below is the implementation of the idea.

## C++

 `// A simple C++ program to``// check for even or odd``#include ``using` `namespace` `std;` `// Returns true if n is``// even, else odd``bool` `isEven(``int` `n)``{``    ` `// n & 1 is 1, then``// odd, else even``return` `(!(n & 1));``}` `// Driver code``int` `main()``{``int` `n = 101;``isEven(n)? cout << ``"Even"` `:``           ``cout << ``"Odd"``;` `return` `0;``}`

## Java

 `// Java program program to``// check for even or odd` `class` `GFG``{``    ``// Returns true if n``    ``// is even, else odd``    ``public` `static` `boolean` `isEven(``int` `n)``    ``{``        ``if``((n & ``1``) == ``0``)``            ``return` `true``;``        ``else``            ``return` `false``;``    ``}``    ` `    ``// Driver code``    ``public` `static` `void` `main(String[] args)``    ``{``        ``int` `n = ``101``;``        ``if``(isEven(n) == ``true``)``            ``System.out.print(``"Even"``);``        ``else``            ``System.out.print(``"Odd"``);``    ``}``}` `// This code is contributed by rishabh_jain`

## Python3

 `# A Python3 code program``# to check for even or odd` `# Returns true if n is even, else odd``def` `isEven(n):``    ` `    ``# n&1 is 1, then odd, else even``    ``return` `(``not``(n & ``1``))``    ` `# Driver code``n ``=` `101``;``print``(``"Even"` `if` `isEven(n) ``else` `"Odd"``)` `# This code is contributed by "Sharad_Bhardwaj".`

## C#

 `// C# program program to``// check for even or odd``using` `System;` `class` `GFG``{``    ``// Returns true if n``    ``// is even, else odd``    ``public` `static` `bool` `isEven(``int` `n)``    ``{``        ``if``((n & 1) == 0)``            ``return` `true``;``        ``else``            ``return` `false``;``    ``}``    ` `    ``// Driver code``    ``public` `static` `void` `Main()``    ``{``        ``int` `n = 101;``        ``if``(isEven(n) == ``true``)``            ``Console.WriteLine(``"Even"``);``        ``else``            ``Console.WriteLine(``"Odd"``);``    ``}``}` `// This code is contributed by vt_m.`

## PHP

 ``

## Javascript

 ``

Output :

`Odd `

This article is contributed by Prabhat Raushan. 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.