Given an array **arr[]** containing **N** numbers. The task is to check whether the bitwise-AND of the given **N** numbers is even or odd.

**Examples**:

Input:arr[] = { 2, 12, 20, 36, 38 }

Output:Even

Input:arr[] = { 3, 9, 17, 13, 15 }

Output:Odd

A **Simple Solution** is to first find the AND of the given N numbers, then check if this AND is even or odd.

A **Better Solution** is based on bit manipulation and Mathematical facts.

- Bitwise AND of any two even numbers is an even number.
- Bitwise AND of any two odd numbers is an odd number.
- Bitwise AND of an even and an odd number is an even number.

Based on the above facts, it can be deduced that if at least one even number is present in the array then the bitwise AND of whole array will be even otherwise odd.

Below is the implementation of the above approach:

## C++

`// C++ implementation of the approach ` `#include <bits/stdc++.h> ` `using` `namespace` `std; ` ` ` `// Function to check if the bitwise AND ` `// of the array elements is even or odd ` `void` `checkEvenOdd(` `int` `arr[], ` `int` `n) ` `{ ` ` ` `for` `(` `int` `i = 0; i < n; i++) { ` ` ` ` ` `// If at least an even element is present ` ` ` `// then the bitwise AND of the ` ` ` `// array elements will be even ` ` ` `if` `(arr[i] % 2 == 0) { ` ` ` ` ` `cout << ` `"Even"` `; ` ` ` `return` `; ` ` ` `} ` ` ` `} ` ` ` ` ` `cout << ` `"Odd"` `; ` `} ` ` ` `// Driver code ` `int` `main() ` `{ ` ` ` `int` `arr[] = { 2, 12, 20, 36, 38 }; ` ` ` `int` `n = ` `sizeof` `(arr) / ` `sizeof` `(arr[0]); ` ` ` ` ` `checkEvenOdd(arr, n); ` ` ` ` ` `return` `0; ` `} ` |

*chevron_right*

*filter_none*

## Java

`// Java implementation of the approach ` `import` `java.io.*; ` ` ` `class` `GFG ` `{ ` ` ` `// Function to check if the bitwise AND ` `// of the array elements is even or odd ` `static` `void` `checkEvenOdd(` `int` `[]arr, ` `int` `n) ` `{ ` ` ` `for` `(` `int` `i = ` `0` `; i < n; i++) ` ` ` `{ ` ` ` ` ` `// If at least an even element is present ` ` ` `// then the bitwise AND of the ` ` ` `// array elements will be even ` ` ` `if` `(arr[i] % ` `2` `== ` `0` `) ` ` ` `{ ` ` ` `System.out.print(` `"Even"` `); ` ` ` `return` `; ` ` ` `} ` ` ` `} ` ` ` `System.out.println(` `"Odd"` `); ` `} ` ` ` `// Driver code ` `public` `static` `void` `main (String[] args) ` `{ ` ` ` `int` `[]arr = { ` `2` `, ` `12` `, ` `20` `, ` `36` `, ` `38` `}; ` ` ` `int` `n = arr.length; ` ` ` ` ` `checkEvenOdd(arr, n); ` `} ` `} ` ` ` `// This code is contributed by @tushil ` |

*chevron_right*

*filter_none*

## Python3

`# Python3 implementation of the approach ` ` ` `# Function to check if the bitwise AND ` `# of the array elements is even or odd ` `def` `checkEvenOdd(arr, n) : ` ` ` ` ` `for` `i ` `in` `range` `(n) : ` ` ` ` ` `# If at least an even element is present ` ` ` `# then the bitwise AND of the ` ` ` `# array elements will be even ` ` ` `if` `(arr[i] ` `%` `2` `=` `=` `0` `) : ` ` ` ` ` `print` `(` `"Even"` `, end ` `=` `""); ` ` ` `return` `; ` ` ` ` ` `print` `(` `"Odd"` `, end ` `=` `""); ` ` ` `# Driver code ` `if` `__name__ ` `=` `=` `"__main__"` `: ` ` ` ` ` `arr ` `=` `[ ` `2` `, ` `12` `, ` `20` `, ` `36` `, ` `38` `]; ` ` ` `n ` `=` `len` `(arr); ` ` ` ` ` `checkEvenOdd(arr, n); ` ` ` `# This code is contributed by AnkitRai01 ` |

*chevron_right*

*filter_none*

## C#

`// C# implementation of the approach ` `using` `System; ` ` ` `class` `GFG ` `{ ` ` ` `// Function to check if the bitwise AND ` `// of the array elements is even or odd ` `static` `void` `checkEvenOdd(` `int` `[]arr, ` `int` `n) ` `{ ` ` ` `for` `(` `int` `i = 0; i < n; i++) ` ` ` `{ ` ` ` ` ` `// If at least an even element is present ` ` ` `// then the bitwise AND of the ` ` ` `// array elements will be even ` ` ` `if` `(arr[i] % 2 == 0) ` ` ` `{ ` ` ` `Console.Write (` `"Even"` `); ` ` ` `return` `; ` ` ` `} ` ` ` `} ` ` ` `Console.Write (` `"Odd"` `); ` `} ` ` ` `// Driver code ` `static` `public` `void` `Main () ` `{ ` ` ` `int` `[]arr = { 2, 12, 20, 36, 38 }; ` ` ` `int` `n = arr.Length; ` ` ` ` ` `checkEvenOdd(arr, n); ` `} ` `} ` ` ` `// This code is contributed by ajit.. ` |

*chevron_right*

*filter_none*

**Output:**

Even

**Time Complexity:** O(N)

Attention reader! Don’t stop learning now. Get hold of all the important DSA concepts with the **DSA Self Paced Course** at a student-friendly price and become industry ready.

## Recommended Posts:

- Check whether bitwise OR of N numbers is Even or Odd
- Queries to check whether bitwise AND of a subarray is even or odd
- Even numbers at even index and odd numbers at odd index
- Total pairs in an array such that the bitwise AND, bitwise OR and bitwise XOR of LSB is 1
- Check whether product of 'n' numbers is even or odd
- Check if a Number is Odd or Even using Bitwise Operators
- Check whether a given number is even or odd
- C program to check whether a given number is even or odd
- Count ways to generate pairs having Bitwise XOR and Bitwise AND equal to X and Y respectively
- Check whether bitwise AND of a number with any subset of an array is zero or not
- Find subsequences with maximum Bitwise AND and Bitwise OR
- Maximize sum of squares of array elements possible by replacing pairs with their Bitwise AND and Bitwise OR
- Sort all even numbers in ascending order and then sort all odd numbers in descending order
- Rotate all odd numbers right and all even numbers left in an Array of 1 to N
- Bitwise AND of all the odd numbers from 1 to N
- Leftover element after performing alternate Bitwise OR and Bitwise XOR operations on adjacent pairs
- Minimum possible Bitwise OR of all Bitwise AND of pairs generated from two given arrays
- Count pairs with bitwise XOR exceeding bitwise AND from a given array
- Generate an array of given size with equal count and sum of odd and even numbers
- Bitwise AND of the sum of prime numbers and the sum of composite numbers in an array

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.

Please Improve this article if you find anything incorrect by clicking on the "Improve Article" button below.