OJ-questions Online Judge questions practice Project Euler: https://projecteuler.net LeetCode: https://leetcode.com Some cool references: Awesome-Algorithm, Huahua's Youtube Channel, LeetCode Algorighm Animation, Leetcode SpreadSheet DP 告别动态规划,连刷 40 道题,我总结了这些套路,看不懂你打我(万字长文)