## The Hopcroft-Karp Algorithm – GT – Computability, Complexity, Theory: Algorithms

The Hopcroft-Karp algorithm goes like this. We first initialize the matching to the empty set, then we repeat the following. First, we build an alternating level graph rooted at the unmatched vertices on the left part of the partition using breadth-first search. Let’s pause for a moment here and see how this works in an

## Vertex Cover – Georgia Tech – Computability, Complexity, Theory: Algorithms

Now we turn to the concept of a vertex cover, which will play a role analogous to the one played by the concept of minimum cut in our discussion of maximum flows. Given a graph, G, we say that S is a vertex cover if every edge is incident on a vertex in S. Thus

## Analysis of Dinic’s Algorithm – GT – Computability, Complexity, Theory: Algorithms

We turn now to the key part of the analysis where we show that each phase of the Dinic algorithm takes V times E time. As with Edmonds-Karp, we will use a level graph. In this case, however, the algorithm actually builds the graph, whereas in Edmonds-Karp we simply used it for the analysis. The