Huffman Coding (Revisited) 🎯

Welcome back! Today, we're diving into the fascinating world of Huffman Coding, a popular data compression algorithm. Let's get started!

What is Huffman Coding? 📝

Huffman Coding is a lossless data compression technique used to encode data using variable-length codes for symbols. The result? Smaller file sizes!

Efficient: Reduces the size of data, especially for texts with frequent repetitions
Lossless: Retains the original data after decompression
Versatile: Used in various data compression algorithms and tools

The Huffman Tree is a binary tree where leaf nodes represent characters and the frequency of their occurrence. We'll build it step-by-step!

markdown

    Frequency
         / \
    A    B
     / \    \
  5    3    4

📝 Note: In our example, A has a frequency of 5, B has a frequency of 4, and there's another character (let's call it C) with a frequency of 3.

Create a node for each character with their respective frequencies.
Combine the two nodes with the lowest frequencies into a new parent node, and make it the root of the new tree. Update the frequencies of the combined nodes to reflect the new total frequencies.

markdown

    Frequency
         / \
    A    B
     / \    \
  5    3     8  // 3 (C) + 5 (remaining A)

Repeat the process until only one node remains: the root of the Huffman Tree!

Now that we have our Huffman Tree, we can start encoding and decoding data.

Traverse the tree from root to leaf node for each character based on their frequency.
Assign a binary code to each leaf node.

Convert the encoded data from binary to decode the original data by traversing the tree from the root, following the binary path.

Create a priority queue of nodes (initialize with all characters and their frequencies)
While the priority queue has more than one node:
- Remove the two nodes with the lowest frequencies from the priority queue.
- Create a new parent node with the sum of their frequencies.
- Add the new parent node back to the priority queue.
The remaining root node is the Huffman Tree.

Huffman Coding is used in various projects like compression utilities, network protocols, and even in PDF files!

Up next, we'll write some code to implement Huffman Coding ourselves! 🚀