Implement an algorithm that returns a cycle in a directed graph _G, if one exists. Write a function, components(g), for undirected graph g, that returns a dictionary mapping each vertex to an...

Implement an algorithm that returns a cycle in a directed graph _G, if one

exists.

Write a function, components(g), for undirected graph
g, that returns a

dictionary mapping each vertex to an integer that serves as an identifier for

its connected component. That is, two vertices should be mapped to the

same identifier if and only if they are in the same connected component.