用广度优先遍历求有向带权图的最短路径

graph.h

#ifndef GRAPH_H
#define GRAPH_H

#include

using namespace std;

class edge;

class vertex		//顶点
{
	friend void connect ( vertex& , vertex& , int );		//建立关系
	friend void bfs (const vertex& , int );					//广度遍历
	friend void bfs ( vertex& , vertex& , int n );
public:
	bool operator!=( const vertex& );
	vertex *pPre = nullptr;					//用于记录路径，指向第一个到达该顶点的顶点。
	int ID = 0;										//顶点的独一无二的序号，构造时给定。

private:
	int in_degree = 0;							//入度
	int out_degree = 0;						//出度
	vector incident_edge;		//关联边的集合

};

class edge				//边
{
	friend void connect ( vertex& , vertex& , int );
	friend void bfs ( const vertex& , int );
	friend void bfs ( vertex& , vertex& , int n );
public:
	edge ( vertex& , int );
private:
	int weight = 0;				//权重
	vertex* pNext = nullptr;		//指向的顶点
};

#endif

graph.cpp

#include"graph.h"

edge::edge ( vertex& v , int w )
{
	weight = w;
	pNext = &v;
}

void connect ( vertex& v1 , vertex& v2 , int w )
{
	v1.out_degree++;
	v2.in_degree++;
	edge e ( v2 , w );
	v1.incident_edge.push_back ( e );
}

bool vertex::operator!=( const vertex& v)
{
	return this->ID != v.ID;
}

main.cpp

#include
#include