图的深度优先和广度优先算法（DFS递归与非递归）

#include "stdafx.h"
#include <stdlib.h>
#include <malloc.h>
#define INFINITY INT_MAX
#define MAX_VEX 20
#define VRType int
#define VertexType char
#define InfoType int
int *visited;
/********************************/
/****      图的结构定义      ****/
/********************************/
typedef enum
{
	DG, 
	DN,
	UDG,
	UDN
}GraphKind;
struct _ArcCell
{
	VRType adj; /* note weight */
	InfoType *info;
};
typedef struct _ArcCell ArcCell, AdjMatrix[MAX_VEX][MAX_VEX];
struct _MGraph
{
	VertexType vexs[MAX_VEX];
	AdjMatrix arcs;
	int vexnum, arcnum;
	GraphKind kind;
};
typedef struct _MGraph MGraph;
/********************************/
/****      栈的结构定义      ****/
/********************************/
struct _node
{
	int ivex;
	struct _node *next;
};
typedef struct _node node, *pnode;
struct _stack
{
	int size;
	pnode ptop;
};
typedef struct _stack stack, *pstack;
/********************************/
/****      堆的结构定义      ****/
/********************************/
struct _queue
{
	pnode front;
	pnode rear;
};
typedef struct _queue queue, *pqueue;
/********************************/
/****         栈的实现       ****/
/********************************/
pstack init_stack(int size)
{
	pnode pn=NULL;
	pstack ps=NULL;
	pn=(pnode)malloc(sizeof(node));
	ps=(pstack)malloc(sizeof(stack));
	pn->ivex=-1;
	pn->next=NULL;
	ps->size=size;
	ps->ptop=pn;
	return ps;
}
int empty_stack(pstack ps)
{
	if(ps->ptop->next==NULL)
		return 1;
	else
		return 0;
}
void push_stack(pstack ps, int ivex)
{
	pnode pn=NULL;
	pn=(pnode)malloc(sizeof(node));
	pn->ivex=ivex;
	pn->next=ps->ptop;
	ps->ptop=pn;
}
int pop_stack(pstack ps)
{
	int ivex=-1;
	pnode pn=NULL;
	if(!empty_stack(ps))
	{
		pn=ps->ptop;
		ps->ptop=ps->ptop->next;
		ivex=pn->ivex;
		free(pn);
	}
	return ivex;
}
/********************************/
/****         堆的实现       ****/
/********************************/
queue init_queue()
{
	pnode pn=NULL;
	queue qu;
	pn=(pnode)malloc(sizeof(node));
	pn->next;
	pn->ivex=-1;
	qu.front=qu.rear=pn;
	return qu;
}
int empty_queue(queue qu)
{
	if(qu.front==qu.rear)
		return 1;
	else
		return 0;
}
void en_queue(queue qu, int ivex)
{
	pnode pn=NULL;
	pn=(pnode)malloc(sizeof(node));
	pn->ivex=ivex;
	pn->next=qu.rear->next;
	qu.rear=pn;
}
int de_queue(queue qu)
{
	int ivex=-1;
	pnode pn=NULL;
	if(!empty_queue(qu))
	{
		pn=qu.front;
		qu.front=qu.front->next;
		ivex=pn->ivex;
		free(pn);
	}
	return ivex;
}
/********************************/
/****         图的实现       ****/
/********************************/
int LocateVex(MGraph g, char ch)
{
	int i;
	for(i=1; i<=g.vexnum; i++)
		if(ch==g.vexs[i])
			return i;
	return -1;
}
MGraph Create_UDG()
{
	int i, j, w, p1, p2;
	char ch1, ch2;
	MGraph g;
	printf("Enter vexnum arcnum: ");
	scanf("%d %d", &g.vexnum, &g.arcnum);
	getchar();
	for(i=1; i<=g.vexnum; i++)
		for(j=1; j<=g.vexnum; j++)
			g.arcs[i][j].adj=g.arcs[j][i].adj=INFINITY; /* UDG should define i-j and j-i */
	printf("Enter %d vex.../n", g.vexnum);
	for(i=1; i<=g.vexnum; i++)
	{
		printf("vex %d: ", i);
		scanf("%c", &g.vexs[i]);
		getchar();
	}
	printf("Enter %d arc.../n", g.arcnum);
	for(i=1; i<=g.arcnum; i++)
	{
		printf("arc %d: ", i);
		scanf("%c %c %d", &ch1, &ch2, &w);
		getchar();
		p1=LocateVex(g, ch1);
		p2=LocateVex(g, ch2);
		g.arcs[p1][p2].adj=g.arcs[p2][p1].adj=w;
	}
	return g;
}
int FirstVex(MGraph g, int i)
{
	int k;
	if(i>=1 && i<=g.vexnum)
		for(k=1; k<=g.vexnum; k++)
			if(g.arcs[i][k].adj!=INFINITY)
				return k;
	return -1;
}
int NextVex(MGraph g, int i, int j)
{
	int k;
	if(i>=1 && i<=g.vexnum && j>=1 && j<=g.vexnum)
		for(k=j+1; k<=g.vexnum; k++)
			if(g.arcs[i][k].adj!=INFINITY)
				return k;
	return -1;
}
void DFS(MGraph g, int i)
{
	int j;
	if(!visited[i])
	{
		visited[i]=1;
		printf("%3c", g.vexs[i]);
		for(j=FirstVex(g, i); j>=1; j=NextVex(g, i, j))
			if(!visited[j])
				DFS(g, j);
	}
}
void DFS_Graph(MGraph g)
{
	int i;
	visited=(int *)malloc((g.vexnum+1)*sizeof(int));
	for(i=1; i<=g.vexnum; i++)
		visited[i]=0;
	for(i=1; i<=g.vexnum; i++)
		if(!visited[i])
			DFS(g, i);
}
void DFS2_Graph(MGraph g)
{
	int i, j, k;
	pstack ps=NULL;
	ps=init_stack(g.vexnum);
	visited=(int *)malloc((g.vexnum+1)*sizeof(int));
	for(i=1; i<=g.vexnum; i++)
		visited[i]=0;
	for(i=1; i<=g.vexnum; i++)
		if(!visited[i])
		{
			visited[i]=1;
			printf("%3c", g.vexs[i]);
			push_stack(ps, i);
			k=i;
			while (!empty_stack(ps))
			{		
				for(j=FirstVex(g, k); j>=1; j=NextVex(g, k, j))
				{
					if(!visited[j])
					{
						visited[j]=1;
						printf("%3c", g.vexs[j]);
						push_stack(ps, j); /* push all visited ivex */
						k=j; /* newer node */
					}					
				}
				k=pop_stack(ps);
			}
		}
}
void BFS_Graph(MGraph g)
{
	int i, j, k;
	queue qu;
	qu=init_queue();
	visited=(int *)malloc((g.vexnum+1)*sizeof(int));
	for(i=1; i<=g.vexnum; i++)
		visited[i]=0;
	for(i=1; i<=g.vexnum; i++)
		if(!visited[i])
		{
			visited[i]=1;
			printf("%3c", g.vexs[i]);
			en_queue(qu, i);
			while (!empty_queue(qu))
			{
				k=de_queue(qu);
				for(j=FirstVex(g, k); j>=1; j=NextVex(g, k, j))
					if(!visited[j])
					{
						visited[j]=1;
						printf("%3c", g.vexs[j]);
						en_queue(qu, j);
					}
			}
		}
}
/********************************/
/****          主函数        ****/
/********************************/
int _tmain(int argc, _TCHAR* argv[])
{
	MGraph g;
	g=Create_UDG();
	printf("/nDFS: "); 
	DFS_Graph(g);       /* recursion */
	printf("/nDFS: "); 
	DFS2_Graph(g);      /* non recursion */
	printf("/nBFS: ");
	BFS_Graph(g);
	printf("/n");
	return 0;
}