链表程序详解Linklist.c

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

typedef int datatype;
typedef struct node/*链表的每一个节点都是结构体*/
{
    datatype data;
    struct node *next; 
}linklist;/*linklist 是struct node 的别名，以后就可以用linklist来替代struct node*/

/*函数声明区*/
linklist * list_create();
int head_insert(linklist *H,datatype value);
int head_delete(linklist *H);
void list_show(linklist *H);
//空----1   非空-----0
int list_empty(linklist *H);
int list_insert(linklist *H,datatype value,int pos);
int list_delete(linklist *H,datatype value);
int list_replace(linklist *H,datatype old,datatype new);
int list_search(linklist *H,datatype value);
void list_recorver(linklist *H);

int main(int argc, const char *argv[])
{
    linklist *H = NULL;
    if((H = list_create()) == NULL)
    {
        printf("list_create failed\n");
        return -1;
    }

    head_insert(H,1);
    head_insert(H,2);
    head_insert(H,3);
    head_insert(H,4);
    head_insert(H,5);
    list_show(H);

    head_delete(H);
    list_show(H);

    list_insert(H,10,2);
    list_show(H);

    list_delete(H,3);
    list_show(H);

    list_replace(H,10,100);
    list_show(H);

    printf("search:%d\n",list_search(H,1));

    list_recorver(H);
    list_show(H);

    return 0;
}

linklist * list_create()
{
    linklist *H = NULL;
    if((H = malloc(sizeof(linklist))) == NULL)
    {
        printf("malloc failed\n");
        return NULL;
    }

    H->next = NULL;//防止野指针。

    return H;
}

int head_insert(linklist *H,datatype value)
{
    linklist *p = NULL;
    if((p = malloc(sizeof(linklist))) == NULL)
    {
        printf("malloc node failed\n");
        return -1;
    }

    p->data = value;

    p->next = H->next;
    H->next = p;

    return 0;
}

void list_show(linklist *H)
{
    while(H->next != NULL)
    {
        printf("%d ",H->next->data);
        H = H->next;
    }
    printf("\n");
}

int head_delete(linklist *H)
{
    linklist *p = H->next;
    if(list_empty(H))
    {
        printf("list is empty\n");
        return -1;
    }
    
    H->next = p->next;
    free(p);
    p = NULL;

    return 0;
}

int list_empty(linklist *H)
{
    if(H->next != NULL)
        return 0;
    else
        return 1;
}

int list_insert(linklist *H,datatype value,int pos)
{
    int i = 0;
    linklist *p = H,*q = NULL;
    while(i < pos && p != NULL)
    {
        p = p->next;
        i++;
    }

    if(p == NULL)
    {
        printf("pos error\n");
        return -1;
    }

    if((q = malloc(sizeof(linklist))) == NULL)
    {
        printf("malloc node failed\n");
        return -1;
    }

    q->data = value;
    q->next = p->next;
    p->next = q;

    return 0;
}

int list_delete(linklist *H,datatype value)
{
    linklist *p = NULL;

    while(H->next != NULL)
    {
        if(H->next->data == value)
        {
            p = H->next;
            H->next = p->next;
            free(p);
            p = NULL;

            return 0;
        }
        else
            H = H->next;
    }

    printf("no value");
    return -1;
}

int list_replace(linklist *H,datatype old,datatype new)
{
    while(H->next != NULL)
    {
        if(H->next->data == old)
        {
            H->next->data = new;
            return 0;
        }
        else
        {
            H = H->next;
        }
    }

    return -1;
}

int list_search(linklist *H,datatype value)
{
    int pos = 0;
    while(H->next != NULL)
    {
        if(H->next->data == value)
            return pos;
        else
        {
            H = H->next;
            pos++;
        }
    }

    printf("no found\n");
    return -1;
}

void list_recorver(linklist *H)
{
    linklist *q = NULL,*p = H->next;
    H->next = NULL;

    while(p != NULL)
    {
        q = p;
        p = p->next;
        q->next = H->next;
        H->next = q;
    }
}