6. 单链表学习记录

[dong@localhost code]$ more list1.c

#define NULL 0
#define LEN sizeof (struct student)

/*2017-01-24： centos下vim不方便输入中文，用SecureCRT远程登录后就可以比
较方便的录入中文了！ */
/*隐式声明与内建函数‘malloc’不兼容 [默认启用],增加头文件说明 */

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

struct student
{
                long num;
                float score;
                struct student * next;
};

int n;




struct student * creat() /*此函数带回一个指向链表头的指针 */
{
                struct student * head;
                struct student * p1,* p2;
                n = 0;
                p1 = p2 = (struct student *)malloc(LEN); /* malloc 开辟一个结点
，让p1、p2都指向它 */

 /*在一般系统中，malloc带回的是指向字符型数据的指针， 这里使用了强制类型
转换的方法，用（struct student *）来把malloc（）带回的指向字符类型数据的
指针强制转换为指向struct student类型数据的指针 */

                scanf("%ld,%f",&p1->num,&p1->score);
                head = NULL;

                while (p1->num!=0)
                                {
                                n=n+1;
                                if(n== 1)head = p1;
                                else p2->next = p1;
                                p2 = p1;
                                p1 = (struct student *)malloc(LEN);
                                scanf("%ld,%f",&p1->num,&p1->score);
                                }

                p2->next = NULL;
                return(head);


}

void print(head)
struct student * head;
{
                struct student *p;
                printf("\nNow,These %d records are:\n",n);
                p = head;
                if(head!=NULL)
                                do
                                {
                                printf("%ld %5.1f\n",p->num,p->score);
                                p = p->next;
                                }while(p!=NULL);
}

main ()
{
  struct student * head;
  printf("input records:\n");
  head=creat();
  print(head);

}

[dong@localhost code]$

[dong@localhost code]$ cc list1.c

[dong@localhost code]$ ./a.out
input records:
85698789,88
0

Now,These 1 records are:
85698789  88.0


::

[dong@localhost code]$ ./a.out
input records:
888888888,85
203,89
5230147,90
8632158,88
863214587,95
5632,72
0

Now,These 6 records are:
888888888  85.0
203  89.0
5230147  90.0
8632158  88.0
863214587  95.0
5632  72.0