vertex.h

/// File: vertex.h
/// This class encapsulates the identifier of a Vertex object and a collection of  Vertex
/// objects in the minimum spanning tree of the graph which are adjacent to this Vertex.
/// information required by Dijkstra’s algorithm, Kruskal’s algorithm and the Breadth First Search algorithm.

#ifndef VERTEX_H
#define VERTEX_H
#include <iostream>
#include <set>

using namespace std;

class Vertex {
public:

    /// No argument constructor.
    Vertex();

    /// Constructor which sets the vertex identifier (useful for indexing into collections of vertices).
    Vertex(unsigned int);

    /// Destructor.
    ~Vertex();

    /// Accessor for this vertex’ identifier
    unsigned int getId();

    /// Adds a Vertex’ identifier to this vertex’ adjacency list.
    /// Used by the Graph::Minimum Spanning Tree method
    void addAdjacency(unsigned int);

    /// Returns a collection of int, being the vertices adjacent to this Vertex.
    /// Used by the Graph::Breadth First Search method
    set<unsigned int>* getAdjacencies();

    /// Mutator for the Discovered field
    void setDiscovered(bool);

    /// Accessor for the Discovered field
    bool isDiscovered();

    /// Mutator for the predecessorId field
    void setPredecessorId(unsigned int);

    /// Accessor for the predecessorId field
    unsigned int getPredecessorId();

    /// Mutator for the minDistance field
    void setMinDistance(double);

    /// Accessor for the minDistance field
    double getMinDistance();

    /// Function operator implementation to provide an ordering for two Vertex instances.
    /// Returns true if the minDistance of the first parameter is greater than that of the second parameter.
    bool operator()(Vertex*, Vertex*);

    /// Provides a string representation of this object. Useful for debugging.
    friend ostream& operator<<(ostream&, Vertex&);

private:
    /// Instance field to store the identifier for this Vertex.
    unsigned int identifier;

    /// Stores vertex identifiers for vertices adjacent to this vertex as discovered
    /// during the Graph::Minimum Spanning Tree method.
    set<unsigned int> adjacencies;

    /// Keeps track of whether or not this vertex has been visited during
    /// Dijkstra’s algorithm or discovered during the Breadth First Search method.
    bool discovered;

    /// Stores the predecessor vertex identifier for path discovery.
    unsigned int predecessorId;

    /// Store the minimum distance from the source to this vertex.
    /// Used by Dijkstra’s algorithm.
    double minDistance;
};

#endif // VERTEX_H