Dynamic Programming lecture #2 - Coin change, double counting

Part 1:    • Dynamic Programming lecture #1 - Fibonacci...  
This is the second of several lectures about Dynamic Programming. I will again go through three problems: Combination Sum, Coin Change (min) and Coin Change (count). The third one is hardest because of double counting. Links to Leetcode in the pinned comment. Watch this lecture if you practice for competitive programming or for coding interviews. Consider turning captions on and setting the speed to x1.25.

Please give me suggestions about the format of a lecture or about topics for future lectures.

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I’m Kamil Dębowski, better known as Errichto. I compete in and organize programming competitions. I make educational streams on Youtube and Twitch. I'm a finalist of ACM-ICPC, Topcoder Open, Facebook Hacker Cup and Google Code Jam. I got a second place in Google Code Jam 2018. I am/was nutella in Codeforces and target in Topcoder.

Watch me if you want to practice for coding interviews, competitive programming or just algorithms in general. I share my thought process, explain everything, and mention similar problems and techniques/algorithms.