I think this is the best lecture among the data structure algorithm lectures. ㅎㅎ I chose Python as my first programming language, so I finished one of the popular Python introductory textbooks on the market, and then I was thinking about what to study more, and I tried to solve coding problems. As I encountered problems that used the concepts of data structures and algorithms, I bought related textbooks and looked them up. However, there were many principles that were difficult to understand just through text, and there were many concepts that I couldn't even understand. Arrays... lists... stacks... queues, etc., and even graph concepts. ㅎㅎ,, Then I chose this lecture among many lectures and watched it. I felt like all of my worries above were solved. The explanations of memory structures, data structures, and other concepts were all visualized, so I was able to understand them quickly, and it was really good that I could directly see the changes in variable values, the order of operations, etc. every time the code was executed, and actually implementing those concepts or applying them to coding problems. I think I will gain confidence in solving Python coding problems in the future. Thank you so much for making this lecture.