Count number of even and odd elements in an array

For the given array of integers, count even and odd elements.

**Examples:**

Input:int arr[5] = {2, 3, 4, 5, 6}Output:Number of even elements = 3 Number of odd elements = 2Input:int arr[5] = {22, 32, 42, 52, 62}Output: Number of even elements = 5 Number of odd elements = 0

**Solution:**

We can also check if a number is odd or even

- By doing AND of 1 and that digit, if the result comes out to be 1 then the number is odd otherwise even.
- By its divisibility by 2. A number is said to be odd if it is not divisible by 2, otherwise its even.

Here, we will check if a number is odd, then we will increment the odd counter otherwise we will increment the even counter.

Below is the implementation of the above approach:

## C++

`// CPP program to count number of even` `// and odd elements in an array` `#include <iostream>` `using` `namespace` `std;` `void` `CountingEvenOdd(` `int` `arr[], ` `int` `arr_size)` `{` ` ` `int` `even_count = 0;` ` ` `int` `odd_count = 0;` ` ` `// loop to read all the values in the array` ` ` `for` `(` `int` `i = 0; i < arr_size; i++) {` ` ` ` ` `// checking if a number is completely` ` ` `// divisible by 2` ` ` `if` `(arr[i] & 1 == 1)` ` ` `odd_count++;` ` ` `else` ` ` `even_count++;` ` ` `}` ` ` `cout << ` `"Number of even elements = "` `<< even_count` ` ` `<< ` `"\nNumber of odd elements = "` `<< odd_count;` `}` `// Driver Code` `int` `main()` `{` ` ` `int` `arr[] = { 2, 3, 4, 5, 6 };` ` ` `int` `n = ` `sizeof` `(arr) / ` `sizeof` `(arr[0]);` ` ` ` ` `// Function Call` ` ` `CountingEvenOdd(arr, n);` `}` |

## Java

`// JAVA program to count number of even` `// and odd elements in an array` `import` `java.io.*;` `class` `GFG {` ` ` `static` `void` `CountingEvenOdd(` `int` `arr[], ` `int` `arr_size)` ` ` `{` ` ` `int` `even_count = ` `0` `;` ` ` `int` `odd_count = ` `0` `;` ` ` `// loop to read all the values in` ` ` `// the array` ` ` `for` `(` `int` `i = ` `0` `; i < arr_size; i++) {` ` ` ` ` `// checking if a number is` ` ` `// completely divisible by 2` ` ` `if` `((arr[i] & ` `1` `) == ` `1` `)` ` ` `odd_count++;` ` ` `else` ` ` `even_count++;` ` ` `}` ` ` `System.out.println(` `"Number of even"` ` ` `+ ` `" elements = "` `+ even_count` ` ` `+ ` `" Number of odd elements = "` ` ` `+ odd_count);` ` ` `}` ` ` `// Driver Code` ` ` `public` `static` `void` `main(String[] args)` ` ` `{` ` ` `int` `arr[] = { ` `2` `, ` `3` `, ` `4` `, ` `5` `, ` `6` `};` ` ` `int` `n = arr.length;` ` ` ` ` `// Function Call` ` ` `CountingEvenOdd(arr, n);` ` ` `}` `}` `// This code is Contributed by anuj_67.` |

## Python3

`# Python3 program to count number of` `# even and odd elements in an array` `def` `CountingEvenOdd(arr, arr_size):` ` ` `even_count ` `=` `0` ` ` `odd_count ` `=` `0` ` ` `# loop to read all the values` ` ` `# in the array` ` ` `for` `i ` `in` `range` `(arr_size):` ` ` `# checking if a number is` ` ` `# completely divisible by 2` ` ` `if` `(arr[i] & ` `1` `=` `=` `1` `):` ` ` `odd_count ` `+` `=` `1` ` ` `else` `:` ` ` `even_count ` `+` `=` `1` ` ` `print` `(` `"Number of even elements = "` `,` ` ` `even_count)` ` ` `print` `(` `"Number of odd elements = "` `,` ` ` `odd_count)` `# Driver Code` `arr ` `=` `[` `2` `, ` `3` `, ` `4` `, ` `5` `, ` `6` `]` `n ` `=` `len` `(arr)` `# Function Call` `CountingEvenOdd(arr, n)` `# This code is contributed by sahishelangia` |

## C#

`// C# program to count number of even` `// and odd elements in an array` `using` `System;` `class` `GFG {` ` ` `static` `void` `CountingEvenOdd(` `int` `[] arr, ` `int` `arr_size)` ` ` `{` ` ` `int` `even_count = 0;` ` ` `int` `odd_count = 0;` ` ` `// loop to read all the values in` ` ` `// the array` ` ` `for` `(` `int` `i = 0; i < arr_size; i++) {` ` ` ` ` `// checking if a number is` ` ` `// completely divisible by 2` ` ` `if` `((arr[i] & 1) == 1)` ` ` `odd_count++;` ` ` `else` ` ` `even_count++;` ` ` `}` ` ` `Console.WriteLine(` `"Number of even"` ` ` `+ ` `" elements = "` `+ even_count` ` ` `+ ` `" Number of odd elements = "` ` ` `+ odd_count);` ` ` `}` ` ` `// Driver Code` ` ` `public` `static` `void` `Main()` ` ` `{` ` ` `int` `[] arr = { 2, 3, 4, 5, 6 };` ` ` `int` `n = arr.Length;` ` ` ` ` `// Function Call` ` ` `CountingEvenOdd(arr, n);` ` ` `}` `}` `// This code is Contributed by anuj_67.` |

## PHP

`<?php` `// PHP program to count number of even` `// and odd elements in an array` `function` `CountingEvenOdd( ` `$arr` `, ` `$arr_size` `)` `{` ` ` `$even_count` `= 0; ` ` ` `$odd_count` `= 0; ` ` ` ` ` `// loop to read all the values in` ` ` `// the array` ` ` `for` `( ` `$i` `= 0 ; ` `$i` `< ` `$arr_size` `; ` `$i` `++) ` ` ` `{` ` ` `// checking if a number is ` ` ` `// completely divisible by 2` ` ` `if` `(` `$arr` `[` `$i` `] & 1 == 1)` ` ` `$odd_count` `++ ; ` ` ` `else` ` ` `$even_count` `++ ; ` ` ` `}` ` ` `echo` `"Number of even elements = "` `,` ` ` `$even_count` `,` `" Number of odd "` `,` ` ` `"elements = "` `,` `$odd_count` `; ` `}` `// Driver Code` ` ` `$arr` `= ` `array` `(2, 3, 4, 5, 6);` ` ` `$n` `= ` `count` `(` `$arr` `);` ` ` `// Function Call` ` ` `CountingEvenOdd(` `$arr` `, ` `$n` `);` `// This code is Contributed by anuj_67.` `?>` |

**Output**

Number of even elements = 3 Number of odd elements = 2

**Time Complexity: **O(n)

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