C语言实现链表

最近闲暇之际，重新看了一下C语言和数据结构，感觉链表很有意思，按照书上的思路自己写了一个重新，实现单向链表的操作，支持增加，删除，查找，读文件操作。先自己保留着，以后用的时候参考。

C代码
/*
* @author: lizhenbin
* @date: 2011-09-14
* @descrption: list operation
*/
#include <stdio.h>
#include <stdlib.h>
#include <conio.h>
#define NULL 0

/* define a link node strut */
struct student
{
    long num;
    struct student *prior; /* define point to the struct */
    struct student *next;
};

/* create struct */
struct student *create()
{
    struct student *head; /* link head and node point */
    struct student *p;
    struct student *q;
    long x;

    head = (struct student*)malloc(sizeof(struct student));
    q = head;
    head->next = NULL;
    printf("\nPlease input node numbers to the list: \n");
    scanf("%ld",&x);
    while(x!=0)
    {
        /* create node */
        p = (struct student*)malloc(sizeof(struct student));
        p->num = x;
        p->next = NULL;
        q->next = p;
        p->prior = q;
        q = p;
        scanf("%ld",&x);
    }
    return head;
}

/* Output list all datas */
void print(struct student *head)
{
    struct student *p;
    p = head->next;
    printf("\nThe list is: ");
    if(p==NULL)
    {
        printf("\nInput list is NULL!");
    }
    while(p!=NULL)
    {
        printf("%ld ", p->num);
        p = p->next;
    }
    printf("\n");
}

/* delete list node */
void del(struct student *head)
{
    struct student *p;
    struct student *q;
    int i;
    int j=0;

    printf("Please input delete position: ");
    scanf("%d", &i);
    if(i<1)
    {
        printf("You input %d error.", i);
        printf("\nTry again, Input nnum: ");
        scanf("%d", &i);
    }
    p = head;
    while(j<=i-1 && p!=NULL)
    {
        p = p->next;
        j++;
    }
    if(p==NULL)
    {
        printf("\nThere is no %d in the list.", i);
        exit(1);
    }
    else
    {
        /* delete list node */
        q = p;
        p->prior->next = p->next;
        p->next->prior = p->prior;
        p = p->next;
        free(q);
    }
}

/* insert list node */
void insert(struct student *head)
{
    struct student *p;
    struct student *q = head;
    int i;
    int j = 0;

    p = (struct student*)malloc(sizeof(struct student));
    printf("\nPlease input the student No you want to insert: ");
    scanf("%ld", &p->num);
    printf("\nInput the student %d position to insert: ",p->num);
    scanf("%d", &i);
    if(i<1)
    {
        printf("\nYou input %d error.", i);
        printf("\nTry again, Input nnum: ");
        scanf("%d", &i);
    }
    while(j<=i-1 && q->next!=NULL)
    {
        q = q->next;
        j++;
    }
    if(q->next==NULL && j!=i)
    {
        p->next = NULL;
        p->prior = q;
        q->next = p;
    }
    else
    {
        q->prior->next = p;
        p->prior = q->prior;
        p->next = q;
        q->prior = q;
    }
}

/* search list node position and data */
void search(struct student *head)
{
    struct student *p;
    long number, i=1, j=0;

    printf("\nPlease input the index you want to search: ");
    scanf("%d", &number);
    p = head->next;
    printf("\nThe number in the li

补充：软件开发 , C语言 ,