In 1972 the speaker invented an algorithm to find the strong components of a directed graph in linear time. The algorithm illustrates the power of depth-first search in solving graph problems. This talk will present the algorithm, along with reflections fifty years later. The 9th Heidelberg Laureate Forum took place from September 18–23, 2022. #HLF22 The Heidelberg Laureate Forum (HLF) is an annual networking conference where 200 carefully selected young researchers in mathematics and computer science spend a week interacting with the laureates of the most prestigious awards in their disciplines: the Abel Prize, ACM A.M. Turing Award, ACM Prize in Computing, Fields Medal, IMU Abacus Medal and Nevanlinna Prize. The opinions expressed in the videos do not necessarily reflect the views of the Heidelberg Laureate Forum Foundation or any other person or associated institution involved in the making and distribution of these videos. More information on the Heidelberg Laureate Forum: https://www.heidelberg-laureate-forum.org/ Follow us on social media! Blog: https://scilogs.spektrum.de/hlf/ Twitter: https://twitter.com/HLForum Instagram: https://www.instagram.com/hlforum/ Facebook: https://www.facebook.com/HeidelbergLaureateForum