教材答案有错误P318_1112 将链表逆序排列，即将链头当链尾，链尾当链头

这个答案的解决方法繁琐，没有本人写的简洁，并且效果底下，do_while中嵌套了while循环，导致函数时间复杂度达到n^2级，而本人的是n级，线性级的。

#include <stdio.h>

#include <stdlib.h>

#include <malloc.h>

#include <string.h>

struct stu

{

    int num;

    struct stu *next;

}*p1,*p2;

struct stu *create(void)

{

    int temp;

    struct stu *head =NULL;

    printf("\ninputnumber:");

   while(scanf"%d",&temp)

    {

p1 = (struct stu *)malloc(struct stu);

if(head==NULL)

    head =p1;//没初始化p2,应该换成句子：p2 = head = p1;

else

    p2->next = p1;

p1->num = temp;

printf("input number:");

p2 = p1;

    }//while

    p2->next =NULL;

    return head;

}

void ouput(struct stu *outhead)

{

    for(p1 =output;p1!=NULL;printf("M",p1->num),p1=p1->next);

}

struct stu * turnBack(struct stu *head)

{

    struct stu *new,*newhead= NULL;

    do{

p2 = NULL;

p1 = head;

while(p1->next!=NULL) p2 = p1,p1 = p1->next;//寻末结点

if(newhead==NULL) newhead = p1,new = newhead->next =p2;

new = new->next = p2;//用new指向旧链表末结点为新链表添加该结点

p2->next = NULL;//表末元素的next指向置空

   }while(head->next!=NULL);

}//turnBack

void main()

{

    struct stu *head;

    head = create();

    printf("The originallist:\n");

    output(head);

    head =turnBack(head);

    printf("\nThe newlist:\n");

    output(head);

    printf("\n");

}