Merge Sort is a classic divide-and-conquer algorithm used to sort elements efficiently. It works by recursively splitting the array into smaller subarrays, sorting them, and then merging the sorted subarrays back together.

⚡ Key Concepts

  1. Divide: Split the array into two halves.
  2. Conquer: Recursively sort each half.
  3. Combine: Merge the sorted halves into a single sorted array.

📊 Time Complexity

  • Best Case: ⌦(n log n)
  • Average Case: ⌦(n log n)
  • Worst Case: ⌦(n log n)

🧠 Why Use Merge Sort?

  • Stable sorting algorithm (preserves the order of equal elements)
  • Efficient for large datasets
  • Works well with linked lists

📌 Step-by-Step Example

  1. Split the array into individual elements.
    Merge_Sort_Split
  2. Merge pairs of elements by comparing and combining them.
    Merge_Sort_Merge
  3. Repeat the merge process until the entire array is sorted.

🧩 Practical Applications

  • Sorting large datasets in databases
  • External sorting for files that don’t fit in memory
  • Implementing in programming languages like Python or Java

For a deeper dive into algorithm analysis, check our guide on Big O Notation. 📚