相關問題及基本理論已於前面的幾篇部落格中說明，現僅僅給出code。

code

/*
	無向圖的構建（鄰接表實現）及其廣度優先遍歷
*/
#include <stdio.h>
#include <stdlib.h>

#define MAX_VERTEX_NUM 30
typedef char VtType;
bool visted[MAX_VERTEX_NUM];			//遍歷標記

typedef struct chain
{
	int vid;							//鄰接表表頭索引
	struct chain* next;
}Queue;									//先入先出佇列
Queue* head=NULL;

typedef struct ARC
{
	int adj;
	struct ARC* nextarc;
}ArcNode;								//表節點

typedef struct
{
	VtType data;
	ArcNode* firstarc;
}VNODE,VList[MAX_VERTEX_NUM];			//一維表頭

typedef struct
{
	VList vertices;
	int vexnum,arcnum;
}VLGraph;								//鄰接表圖

void AddArc(VLGraph &G,int m,int n)		//表中新增m結點到n結點的路徑
{
	ArcNode* np,*curp,*save;

	np=(ArcNode*)malloc(sizeof(ArcNode));
	np->adj=n;
	np->nextarc=NULL;

	curp=G.vertices[m].firstarc;
	if(curp==NULL)
	{
		G.vertices[m].firstarc=np;		//第一個節點為空直接新增
	}
	else
	{
		while(curp->adj < np->adj)		//不為空時，後移實現節點索引的遞增排列
		{
			save=curp;
			curp=curp->nextarc;
			if(curp==NULL)
			{
				break;
			}
		}
		if(curp==NULL)
		{
			save->nextarc=np;
		}
		else
		{
			if(curp==G.vertices[m].firstarc)
			{
				save=G.vertices[m].firstarc;
				G.vertices[m].firstarc=np;
				np->nextarc=save;
			}
			else
			{
				save->nextarc=np;
				np->nextarc=curp;
			}
		}
	}
}

void CreateG(VLGraph &G)					//建立無向圖
{
	int i;

	G.vexnum=8;
	G.arcnum=9;

	for(i=0;i<G.vexnum;i++)
	{
		G.vertices[i].firstarc=NULL;
		G.vertices[i].data=97+i;
	}
	
	AddArc(G,0,1);
	AddArc(G,1,0);

	AddArc(G,3,1);
	AddArc(G,1,3);

	AddArc(G,3,7);
	AddArc(G,7,3);

	AddArc(G,4,7);
	AddArc(G,7,4);

	AddArc(G,4,1);
	AddArc(G,1,4);

	AddArc(G,0,2);
	AddArc(G,2,0);

	AddArc(G,2,5);
	AddArc(G,5,2);

	AddArc(G,2,6);
	AddArc(G,6,2);

	AddArc(G,5,6);
	AddArc(G,6,5);

	return;
}

void ShowVlist(VLGraph G)					//鄰接表輸出
{
	int i;
	ArcNode* curp;

	printf("The adjacent list is:\n");
	for(i=0;i<G.vexnum;i++)
	{
		printf("%c",G.vertices[i].data);
		curp=G.vertices[i].firstarc;
		while(curp!=NULL)
		{
			printf("-->%d",curp->adj);
			curp=curp->nextarc;
		}
		printf("-->NULL\n");
	}
	return;
}

void BFS(VLGraph G,int v)					//廣度優先遍歷遞迴函式
{
	ArcNode* curp;
	Queue* temp,*newnode;

	if(visted[v]!=true)
	{
		printf("%c ",G.vertices[v].data);
		visted[v]=true;
	}
	curp=G.vertices[v].firstarc;
	while(curp!=NULL)
	{
		if(visted[curp->adj]!=true)
		{
			printf("%c ",G.vertices[curp->adj].data);
			visted[curp->adj]=true;
			if(head==NULL)
			{
				head=(Queue*)malloc(sizeof(Queue));
				head->vid=curp->adj;
				head->next=NULL;
			}
			else
			{
				temp=head;
				while(temp->next=NULL)
				{
					temp=temp->next;
				}
				newnode=(Queue*)malloc(sizeof(Queue));
				newnode->vid=curp->adj;
				newnode->next=NULL;
				temp->next=newnode;
			}
		}
		curp=curp->nextarc;
	}

	while(head!=NULL)
	{
		temp=head;
		head=head->next;
		BFS(G,temp->vid);
		free(temp);
	}

	return;
}

void BFSTraverse(VLGraph G)					//廣度優先遍歷介面函式
{
	int i;

	printf("The breadth traverse result is:\n");
	for(i=0;i<G.vexnum;i++)
	{
		visted[i]=false;
	}
	for(i=0;i<G.vexnum;i++)
	{
		if(visted[i]==false)
		{
			BFS(G,i);
		}
	}
	return;
}

int main(void)
{
	VLGraph G;

	CreateG(G);
	ShowVlist(G);
	printf("\n");
	BFSTraverse(G);
	printf("\n\n");

	system("pause");
	return 0;
}