c语言快慢指针之找未知长度单链表中间结点 的值并显示

#include <stdio.h>

#include<malloc.h>

#include<time.h>

#define Max 5

typedef struct cursor

{
int data;
struct cursor *next;

}cursor;

cursor *initList();

void findList(cursor head);

void showList(cursor head);

void showList(cursor head)

{
cursor *p;

p=head.next;

while(p!=NULL)
{
printf("%5d",p->data);
p=p->next;
}
printf("\n");

}

void findList(cursor head)

{
cursor *mid;
cursor *fast;
cursor *p;
fast=head.next;
mid=head.next;
while(fast->next!=NULL)
{

if(fast->next->next!=NULL)
{
fast=fast->next->next;
mid=mid->next;
}
else
{
fast=fast->next;
}
}
printf("%d",mid->data);

}

cursor *initList()

{
cursor *head=NULL;
cursor *p=NULL,*q=NULL;
int k=0;
head=(cursor *)(malloc(sizeof(cursor)));

while(k<Max)
{
q=(cursor *)(malloc(sizeof(cursor)));
k++;
if(k==1)
{
head->next=q;
}
else
{
p->next=q;
}
p=q;
p->data=rand()%100+1;

}
p->next=NULL; 

return head;

}

int main()

{
cursor *head=NULL;
srand(time(NULL));

    head=initList();

 

    showList(*head);

    findList(*head);

}