Data Structures and Algorithms with Python | Free DSA with Python Course - DSA Python 2025 - Word Ladder | BFS for Shortest Transformation | Leetcode 127 - Part 129 [Hindi]

🚀 Welcome to Part 129 of Code & Debug’s DSA Python Course 2025! In this lecture, we solve Leetcode 127: Word Ladder, where we find the shortest transformation sequence from beginWord to endWord by changing one character at a time — and every intermediate word must be in the given word list. We solve it using an efficient Breadth-First Search (BFS) approach. 📚 What you’ll learn in this video: ✅ Understanding the word transformation graph ✅ BFS logic to find the shortest path ✅ Dynamic generation of all possible one-character transformations ✅ Using a set for fast lookups and removal ✅ Full dry run, time and space complexity analysis 💡 Why is this important? This problem is a textbook example of graph BFS in disguise. It teaches you how to model non-obvious problems as graphs — a crucial skill for interviews and real-world applications involving transformations, routing, and state-space exploration. 👉 Practice the problem on Leetcode: 🔗 https://leetcode.com/problems/word-ladder/ 👉 Refer to the article for better understanding: 📌 https://codeanddebug.in/blog/word-ladder-leetcode-127/ 👉 📄 Access the full YouTube DSA Playlist Sheet (All Questions in Order): 🔗 https://docs.google.com/spreadsheets/d/1AWE15Fy3wD2iqu2vjK_R7cCiuvSsjYQclcdZmHpF66o/edit?usp=sharing 👉 Enroll in this FREE DSA Python course here: 🔗 https://codeanddebug.in/course/master-dsa-with-leetcode 👉 Enroll for Self-Paced Advanced DSA course here: 🔗 https://codeanddebug.in/course/zero-to-hero-python-dsa 🙏 Thank you for supporting Code & Debug! Don’t forget to like, share, and subscribe to our channel. Hit the 🔔 bell icon to stay updated with our latest lectures. #WordLadder #Leetcode127 #GraphBFS #StringTransformation #ShortestPath #PythonDSA #DSAPythonCourse #CodeAndDebug #DSA2025 #CodingInterviews #Part129