There are many pages on the Internet to help you do this, but I wanted to add it to my blog, if only for my own ease of reference.
Have you somehow misplaced or forgotten your MySQL root user password? Here’s an easy way to reset it. Replace any absolute paths that are not common to your operating system with your respective application paths:
A few years ago I had an interesting interview question: Given a graph, determine whether there are any cyclical relationships between the nodes. This graph also has simple paths/edges, in that all edges go in one direction, i.e. they are not bidirectional. So this graph has a beginning node and an end node.
Another way to ask the question is, given a graph, determine whether or not it is a tree structure. In graph theory, a tree structure is an undirected graph where two verticies are connected by exactly one simple path. (Ref: http://en.wikipedia.org/wiki/Tree_(graph_theory))