Sort Array by Parity: A Comprehensive Guide 🎯

Welcome to CodeYourCraft's guide on Sorting Array by Parity! Today, we'll dive into the fascinating world of Data Structures and Algorithms, focusing on a fun and practical problem - sorting an array based on its elements' parity (even or odd numbers). Let's get started! 🚀

What is Array Parity? 📝

Parity is a term used in mathematics to describe the property of having an even or odd number of items. In the context of arrays, we'll use parity to sort the elements based on whether they are even or odd numbers.

Why Sort Arrays by Parity? 💡

Sorting arrays by parity can be a useful exercise to understand array manipulation and sorting algorithms. It may also appear in real-world projects, such as sorting large datasets, where optimized solutions can significantly improve performance.

Let's Sort! 🔢

Simple Approach: Two Passes 📝

In this method, we'll go through the array twice: first to separate even and odd numbers, and second to arrange them.

python

def sort_array_by_parity(arr):
    even = []
    odd = []
    for num in arr:
        if num % 2 == 0:  # if the number is even
            even.append(num)
        else:  # if the number is odd
            odd.append(num)
    return even + odd  # even numbers first, followed by odds

💡 Pro Tip: This method is simple but inefficient for large arrays, as it requires two passes.

Efficient Approach: One Pass (Sorting Algorithm) 🎯

We'll now use a popular sorting algorithm, QuickSort, to achieve our goal. QuickSort is a divide-and-conquer sorting algorithm that works well for large datasets.

python

def quicksort(arr, left, right):
    if left < right:
        partition_index = partition(arr, left, right)
        quicksort(arr, left, partition_index - 1)
        quicksort(arr, partition_index + 1, right)

def partition(arr, left, right):
    pivot = arr[right]
    i = left
    for j in range(left, right):
        if arr[j] <= pivot:
            arr[i], arr[j] = arr[j], arr[i]
            i += 1
    arr[i], arr[right] = arr[right], arr[i]
    return i

def sort_array_by_parity(arr):
    quicksort(arr, 0, len(arr) - 1)
    return [num for num in arr if num % 2 == 0] + [num for num in arr if num % 2 != 0]

💡 Pro Tip: This method sorts the array in a single pass, making it more efficient for large datasets.

Time for a Quiz! 🧮

By now, you should have a good understanding of sorting arrays by parity. Happy coding, and don't forget to check back for more exciting lessons at CodeYourCraft! 🤖👩‍💻🚀