Competitive Programming in Python Quotes

“For this, the algorithm computes two values for each vertex v, the order number dfs_num[ v], attributed at the beginning of the processing of the vertex, and dfs_min[ v]. The latter value is defined as the minimum of dfs_num[ u] over all the vertices u that are not already in a strongly connected component—and hence still waiting—and reachable from v by a sequence of tree arcs, eventually followed by a single back arc. This value is defined as”
― Christoph Dürr, Competitive Programming in Python: 128 Algorithms to Develop your Coding Skills

“depth-first search enters into a component C by a first vertex v0, and then explores all the vertices and eventually also the components reachable from C. Vertex v0 is processed after all its descendants in the DFS tree. By construction, at the moment of the final processing of v0, clearly the stack waiting contains above v0 all the vertices of C. The vertex v0 is known as the representative of C. The vertices”
― Christoph Dürr, Competitive Programming in Python: 128 Algorithms to Develop your Coding Skills