Data Structures and Algorithms with Python | Free DSA with Python Course - DSA Python 2025 - Word Ladder II | All Shortest Paths Using BFS | Leetcode 126 - Part 130 [Hindi]

🚀 Welcome to Part 130 of Code & Debug’s DSA Python Course 2025! In this lecture, we tackle Leetcode 126: Word Ladder II, where we’re asked to return all shortest transformation sequences from beginWord to endWord by changing one character at a time. This is an extension of the Word Ladder problem, requiring careful use of level-wise BFS and path tracking. 📚 What you’ll learn in this video: ✅ Modeling the word transformation as a graph ✅ Generating all valid sequences using BFS with queue of lists ✅ Tracking each word only once per level to ensure shortest paths ✅ Smart pruning with wordSet and chosen_words ✅ Time & space complexity analysis 💡 Why is this important? This problem tests your ability to not just find one shortest path, but enumerate all shortest paths in a graph-like structure — making it highly relevant for interview rounds at top tech companies. 👉 Practice the problem on Leetcode: 🔗 https://leetcode.com/problems/word-ladder-ii/ 👉 Refer to the article for better understanding: 🔗 https://codeanddebug.in/blog/word-ladder-ii-leetcode-126/ 👉 📄 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. #WordLadderII #Leetcode126 #ShortestPaths #GraphBFS #PythonDSA #DSAPythonCourse #CodeAndDebug #DSA2025 #AllPathsBFS #CodingInterviews #Part130