图的存储—链表

#include <stdio.h>
#include <stdlib.h>

#define N 5

typedef struct _node_
{
 int vertex;
 struct _node_ *next;
} linknode, *linklist;

void AddEdge(linklist h, int vertex)
{
 linklist p;

 while ((h->next != NULL) && (h->next->vertex < vertex)) h = h->next;
 p = (linklist)malloc(sizeof(linknode));
 p->vertex = vertex;
 p->next = h->next;
 h->next = p;

 return ;
}

int FirstAdj(linknode s[], int u)
{
 return s[u].next->vertex;
}

int NextAdj(linknode s[], int u, int v)
{
 linklist p;

 p = s[u].next;
 while (p->vertex != v) p = p->next;
 p = p->next;

 return (NULL == p ? -1 : p->vertex);
}

int main()
{
 int i, j;
 linknode s[N] = {{0}};
 linklist p;

 while (scanf("%d,%d", &i, &j) == 2)
 {
  AddEdge(s+i, j);
  AddEdge(s+j, i);
 }

 for (i=0; i<N; i++)
 {
  printf("V%d : ", i);
  p = s[i].next;
  while (p != NULL)
  {
   printf("V%d ", p->vertex);
   p = p->next;
  }
  printf("\n");
 }

 return 0;
}