LeetCode 122: Best Time to Buy and Sell Stock II | Python Solution | Greedy Algorithm

🔍 In this problem, we need to find the maximum profit by buying and selling stocks multiple times with the constraint that we must sell before buying again. #leetcode #stocktrading #greedyalgorithm #pythonsolution ⏱️ **Time Complexity**: O(n) - we only need a single pass through the price array 🗂️ **Space Complexity**: O(1) - constant extra space used ## Timestamps 00:00 - Understanding problem statement 01:19 - Optimized solution explained 02:50 - Big O Notation calculated 03:15 - Python code walk-through 03:53 - Solution analysis - runtime + memory ## Key Concepts 📌 Greedy Algorithm 📌 Array Traversal 📌 Profit Maximization 📌 Stock Trading Problems ## Main Learning Points 💡 How to identify opportunities for multiple transactions 💡 Why a greedy approach works in this scenario 💡 Simplifying complex problems with intuitive solutions 💡 Common patterns in stock trading problems ## Related Problems - LeetCode 121: Best Time to Buy and Sell Stock - LeetCode 123: Best Time to Buy and Sell Stock III - LeetCode 188: Best Time to Buy and Sell Stock IV - LeetCode 309: Best Time to Buy and Sell Stock with Cooldown ## Target Audience This video is designed for coding interview candidates, software engineers preparing for technical interviews, and anyone interested in algorithmic problem-solving with Python. #codinginterview #interviewprep ## Prerequisites - Basic Python knowledge - Understanding of arrays and loops - Familiarity with greedy algorithms (helpful but not required) ## Useful Links 📊 LeetCode Problem: https://leetcode.com/problems/best-time-to-buy-and-sell-stock-ii/ 💻 Solution Code: https://leetcode.com/problems/best-time-to-buy-and-sell-stock-ii/solutions/6831527/greedy-solution-in-python-with-video-exp-5z4m ## Additional Tips - Focus on the simplicity of the approach - you only need to add up all price increases - Explain why peak-valley approach and simple one-pass solution are equivalent - Visualize the stock prices as a graph to make the solution more intuitive ## Call to Action If you found this solution helpful, please hit the like button and subscribe for weekly LeetCode solutions! Share your approaches or questions in the comments below, and let me know which problems you'd like me to cover next. #pythontutorial #algorithmsanddata