学习数据结构基础，如有错误，请指正。

（图的广度优先遍历算法部分，存在错误，请高手帮小弟看下）

/************************************************************************
 数据结构：图的实现，并对其进行深度优先、广度优先遍历
************************************************************************/
#ifndef __GRAPH_H__
#define __GRAPH_H__

typedef struct ArcNode_stru
{
	int index;
	struct ArcNode_stru *next;
} ArcNode;

typedef struct VNode_stru
{
	int data;
	ArcNode *firstArc;
} VNode;

class Graph
{
public:
	Graph();
	~Graph();

	void creatGraph();
	int firstAdj(int id);
	int nextAdj(int id);
	void depthFirstSearch(int id);
	void breadthFirstSearch(int id);

	void travel_DFS();
	void travel_BFS();
private:
	VNode G[5];
	int visited[5];

};

#endif // __GRAPH_H__


#include "Graph.h"
#include <iostream>
#include <list>
using std::cout;
using std::cin;
using std::endl;
using std::list;

Graph::Graph()
{
	creatGraph();
}
Graph::~Graph()
{
	delete []G;
}

void Graph::creatGraph()
{
	cout<<"input five vertex data:";
	for (int i=0;i<5;++i)
	{
		cin>>G[i].data;
		G[i].firstArc = NULL;

		visited[i] = 0;
	}

	int e;
	ArcNode *node,*preNode;
	for (int i=0;i<5;++i)
	{
		cout<<"input "<<i+1<<"th vertex's edges:"<<endl;
		cin>>e;
		
		while(e != -1)
		{
			node = new ArcNode();
			node->index = e;
			node->next = NULL;
			if (G[i].firstArc == NULL)
			{
				G[i].firstArc = node;
			}
			else
			{
				preNode->next = node;
			}
			preNode = node;

			cin>>e;
		}

	} // end for
}
int Graph::firstAdj(int id)
{
	if (G[id].firstArc != NULL)
	{
		return G[id].firstArc->index;
	}
	return -1;
}
int Graph::nextAdj(int id)
{
	ArcNode *p = G[id].firstArc;
	while (p != NULL)
	{
		if ( visited[p->index] == 1)
		{
			p = p->next;
		}
		else
		{
			return p->index;
		}
	}

	return -1;
}

// 仅适用于连通图
void Graph::depthFirstSearch(int id)
{
	cout<<G[id].data;
	visited[id] = 1;

	int tmp_id = this->firstAdj(id);
	while( tmp_id != -1)
	{
		if (visited[tmp_id] == 0)
		{
			this->depthFirstSearch(tmp_id);
		}
		tmp_id = this->nextAdj(id);
	}
}

// 仅适用于连通图

// 存在错误，请指教
void Graph::breadthFirstSearch(int id)
{
	cout<<G[id].data;
	visited[id] = 1;

	int index = -1;
	list<int> *q = new list<int>;
	q->push_back(id);
	while(0 != q->size() )
	{
		int count = q->size();
		list <int>::iterator item = q->begin();
		list <int>::iterator pre_item = q->begin();
		for (;item!=q->end();++item)
		{
			pre_item = item;
		}
		index = *pre_item;

		int tmp = this->firstAdj(index);
		while (tmp != -1)
		{
			if (visited[tmp] == 0)
			{
				cout<<G[tmp].data;
				visited[tmp] = 1;
				q->push_back(tmp);
			}

			tmp = this->nextAdj(index);
		}
		tmp = this->nextAdj(index);
	}

}

void Graph::travel_DFS()
{
	for (int i=0;i<5;++i)
	{
		if (visited[i] == 0)
		{
			this->depthFirstSearch(i);
		}
	}
}
void Graph::travel_BFS()
{
	for (int i=0;i<5;++i)
	{
		if (visited[i] == 0)
		{
			this->breadthFirstSearch(i);
		}
	}
}

void main()
{
	Graph *g = new Graph();
	//g->travel_DFS();
	g->travel_BFS();

	getchar();
}


// end