无向图邻接表深度优先函数修改

Question

从文件读取无向图邻接表，进行深度优先遍历

#include <stdio.h>
#include <stdlib.h>
#define MAX 100
//定义邻接表
typedef struct node{
    int adjvex;//顶点编号
    struct node *next;//指向下一个结点
}edgenode;//
typedef struct vnode{
    int vertex;//顶点
    edgenode *firstedge;//指向第一个表结点
}vertexnode,AdjList[MAX];//头结点
typedef struct{
    AdjList vertices; //顶点数组
    int vexnum;//顶点数
    int arcnum;//弧的条数
}Graph;
int CreatGraph(Graph &G)//从文件读取并输出邻接表
{
    FILE *fp;edgenode *p;
    if((fp=fopen("graph.txt","r"))==NULL)
    {
      printf("文件打开失败\n");
      return 0;
    }

    fscanf(fp,"%d",&G.vexnum);
    G.arcnum=G.vexnum+1;
    printf("顶点个数%d\n",G.vexnum);
    int i;
    for (i = 1; i <= G.vexnum; i++) 
    {
      G.vertices[i].vertex = i ;
      G.vertices[i].firstedge = NULL;
 
      int a;
      while (1) 
      {
       fscanf(fp, "%d", &a);
       if (a == 0) break;
       else
        {
           p = (edgenode *)malloc(sizeof(edgenode));
           p->adjvex = a;
           p->next = G.vertices[i].firstedge;
           G.vertices[i].firstedge = p;
        }
       }
    }

    fclose(fp);

    //输出邻接表
    printf("创建无向图G2邻接表如下：\n");
    for(i=1;i<=G.vexnum;i++)
    {
       
        p=G.vertices[i].firstedge;//指向第一个表结点
        while(p!=NULL)
        {
          printf("%d->",p->adjvex);
          p=p->next;
        }
        printf("NULL\n");
    }
    return 1;
}
int Firstadjvex(Graph G,int v)//在邻接表中找结点v的第一个邻接点
{
 edgenode *p;
 p=G.vertices[v].firstedge;
 if(p)
     return (p->next->adjvex);
 else
     return 0;
}
int Nextadjvex(Graph G,int v,int w)//在邻接表中找结点v继邻接点w后的第一个结点
{
   edgenode *p;int i,j;
   p=G.vertices[v].firstedge;
   while(p)
   {
    i=p->next->adjvex;
    if(i==w)
        break;
   }
   j=Firstadjvex(G,i);
   return j;
}
void DFS(Graph G,int v,int visited[])
{
    printf("%d",G.vertices[v].vertex);
    visited[v]=1;int w;
    for(w= Firstadjvex(G,v);w;w=Nextadjvex(G,v,w))
        if(visited[w]==0)
            DFS(G,w,visited);
}
void DFStravel(Graph G)
{
    printf("G2深度优先遍历如下\n");
    int visited[MAX];
    int i;
    for(i=1;i<=G.vexnum;++i)
        visited[i]=0;
    for(i=1;i<=G.vexnum;++i)
        if(visited[i])
            DFS(G,i,visited);
}
int main(void)
{
    Graph G;
    G=*(Graph*)malloc(sizeof(Graph));
      CreatGraph(G);
    DFStravel(G);
    return 0;
}

运行结果只有一行G2深度优先遍历如下，请问出错在哪里了呢？如何修改？
文本文档内容为
3
3 2 1 0
3 1 2 0
2 1 3 0

Answer 1

#include <stdio.h>
#include <stdlib.h>
#define MAX 100
//定义邻接表
typedef struct node{
    int adjvex;//顶点编号
    struct node *next;//指向下一个结点
}edgenode;//
typedef struct vnode{
    int vertex;//顶点
    edgenode *firstedge;//指向第一个表结点
}vertexnode,AdjList[MAX];//头结点
typedef struct{
    AdjList vertices; //顶点数组
    int vexnum;//顶点数
    int arcnum;//弧的条数
}Graph;
int CreatGraph(Graph &G)//从文件读取并输出邻接表
{
    FILE *fp;edgenode *p;
    if((fp=fopen("graph.txt","r"))==NULL)
    {
      printf("文件打开失败\n");
      return 0;
    }
 
    fscanf(fp,"%d",&G.vexnum);
    G.arcnum=G.vexnum+1;
    printf("顶点个数%d\n",G.vexnum);
    int i;
    for (i = 1; i <= G.vexnum; i++) 
    {
      G.vertices[i].vertex = i ;
      G.vertices[i].firstedge = NULL;
 
      int a;
      while (1) 
      {
       fscanf(fp, "%d", &a);
       if (a == 0) break;
       else
        {
           p = (edgenode *)malloc(sizeof(edgenode));
           p->adjvex = a;
           p->next = G.vertices[i].firstedge;
           G.vertices[i].firstedge = p;
        }
       }
    }
 
    fclose(fp);
 
    //输出邻接表
    printf("创建无向图G2邻接表如下：\n");
    for(i=1;i<=G.vexnum;i++)
    {
       
        p=G.vertices[i].firstedge;//指向第一个表结点
        while(p!=NULL)
        {
          printf("%d->",p->adjvex);
          p=p->next;
        }
        printf("NULL\n");
    }
    return 1;
}
int Firstadjvex(Graph G, int v) {
    edgenode *p = G.vertices[v].firstedge;
    if (p != NULL)
        return p->adjvex;
    else
        return 0;
}

int Nextadjvex(Graph G, int v, int w) {
    edgenode *p = G.vertices[v].firstedge;
    while (p != NULL) {
        if (p->adjvex == w) {
            if (p->next != NULL) {
                return p->next->adjvex;
            }
            break;
        }
        p = p->next;
    }
    return 0;
}

void DFS(Graph G,int v,int visited[])
{
    printf("%d",G.vertices[v].vertex);
    visited[v]=1;int w;
    for(w= Firstadjvex(G,v);w;w=Nextadjvex(G,v,w))
        if(visited[w]==0)
            DFS(G,w,visited);
}
void DFStravel(Graph G) {
    printf("G2深度优先遍历如下\n");
    int visited[MAX];
    int i;
    for (i = 1; i <= G.vexnum; ++i)
        visited[i] = 0;
    for (i = 1; i <= G.vexnum; ++i)
        if (!visited[i])
            DFS(G, i, visited);
}

int main(void)
{
    Graph G;
    if (!CreatGraph(G)) {
        printf("创建图失败。\n");
        return 1;
    }
    DFStravel(G);
    return 0;
}