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DSA in Python – Letter Combinations of a Phone Number | Backtracking | Leetcode 17 – Part 79 [Hindi]

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🚀 Welcome to Part 79 of Code & Debug’s DSA in Python Course!

In this lecture, we solve Leetcode 17: Letter Combinations of a Phone Number, a classic Recursion & Backtracking problem where we generate all possible letter combinations from a digit string based on the classic phone keypad layout.

📚 What you’ll learn in this video:
✅ Understanding the digit-to-character mapping (like a mobile keypad)
✅ Recursive Backtracking approach to generate all combinations
✅ Efficient traversal through recursion tree
✅ Time and space complexity analysis
✅ Handling edge cases like empty input

💡 Why is this important?
This problem is a great way to learn backtracking with character sets, which is key in solving combinatorics, permutation generation, and string construction problems — often asked in FAANG interviews.

👉 Link to solve this question:
https://leetcode.com/problems/letter-combinations-of-a-phone-number/description/

👉 Refer the article below for better understanding:

Letter Combinations of a Phone Number | Leetcode 17 | Optimal Solution in Python

👉 📄 Access the full YouTube DSA Playlist Sheet (All Questions in Order):
🔗 https://docs.google.com/spreadsheets/d/1AWE15Fy3wD2iqu2vjK_R7cCiuvSsjYQclcdZmHpF66o/edit?usp=sharing

👉 Enroll in the free DSA Python course here:
https://codeanddebug.in/course/master-dsa-with-leetcode

👉 Enroll for Self-Paced Advance 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.

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