Algorithms

LeetCode is the gold standard website for algo problems that might show up in interviews: you can sort by difficulty or filter by topic: https://leetcode.com/

A TechLead video on top "hard" interview algorithms: https://www.youtube.com/watch?v=QGVCnjXmrNg&t=519s

A video showing the winner of the Google Kickstart Round A 2020: https://www.youtube.com/watch?v=uGrBHohIgQY

Graph Theory Tutorial from a Google Engineer: https://www.youtube.com/watch?v=09_LlHjoEiY