$6.(10$ pts $)$ Given a directed graph and a vertex $\backslash ($ v $\backslash ),$ write an algorithm to check whether the vertex $\backslash ($ v $\backslash )$ can be reached from all vertices in the graph. Assume the graph is represented as an adjacency list. Before developing your algorithm, give an outline of the steps in your solution strategy. Give the runtime analysis of your algorithm.