程序代码：

#include<stdio.h>
#include<string.h>
#define LA 4
#define LB 5
struct student
{
    int num;
    char name[8];
    struct student *next;
}a[LA],b[LB];
void main()
{
    struct student a[LA]={{101,"Wang"},{102,"Li"},{105,"Zhang"},{106,"Wei"}};
    struct student b[LB]={{103,"Zhang"},{104,"Ma"},{105,"Chen"},{107,"Guo"},{108,"Lui"}};
    int i;
    struct student *p,*p1,*p2,*head1,*head2;
    head1=a;
    head2=b;

    printf("list A:\n");
    p1=head1;
    for(p1=head1,i=1;i<=LA;i++)
    {
        if(i<LA)
            p1->next=a+i;
        else
            p1->next=NULL;
        printf("%4d%8s\n",p1->num,p1->name);
        if(i<LA)
        p1=p1->next;


    }
    printf("\n list B:\n");

    for(p2=head2,i=1;i<=LB;i++)
    {
        if(i<LB)
            p2->next=b+i;
        else
            p2->next=NULL;
        printf("%4d%8s\n",p2->num,p2->name);
        if(i<LB)
            p2=p2->next;

    }
    p1=head1;
    while(p1!=NULL)
    {
        p2=head2;
        while((p1->num!=p2->num)&&(p2->next!=NULL))
        {
            p2=p2->next;
        }
        if(p1->num==p2->num)
        {
            if(p1=head1)
                head1=p1->next;
            else
            {
                p->next=p1->next;//这句代码和下面的不要感觉也行，不知道对不对
                p1=p1->next;
            }
        }
        else
        {
            p=p1;
            p1=p1->next;
        }
   
    }
    printf("\nresult:\n");
    p1=head1;
    while(p1!=NULL)//
    {
        printf("%4d%8s\n",p1->num,p1->name);
        p1=p1->next;
    }
    //这样能输出感觉不行，不知道p1->next指向谁，如果这样可以的话那上面的输出为何搞得那么复杂，我试过了上面的输出如果用这个的话是不行的话，那为什么这里还要用这 代码，不是自相矛盾吗？

}