From Definition to Abstraction
A graph $G = (V, E)$ consists of a nonempty set $V$ of vertices (or nodes) and a collection $E$ of edges (or arcs).
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Open the starter code and look at the Graph.java
which defines the Graph interface:
/**
* Graph ADT.
*
* @param <V> Vertex element type.
* @param <E> Edge element type.
*/
public interface Graph<V, E> {
// Operations not shown
}
The Graph interface declaration looks a lot like the Mathematical definition of Graph but be careful as V
and E
here are not collection of vertices/edges. They are generic type of the data you store in a vertex or in an edge.
In fact, we define abstractions for Vertex and Edge.