title: Longest path in a DAG
body: <p>To find the longest path in a DAG, I'm aware of 2 algorithms: algo 1: do a topological sort + use dynamic programming on the result of the sort ~ or ~ algo 2: enumerate all the paths in the DAG using DFS, and record the longest. It seems like enumerating all the paths with DFS has better complexity than algo 1. Is that true?</p>