C語言實現改進版單鏈表

相比一般鏈表，這種鏈表實現起來更加方便，也比較靈活
這個實現是從下面這個視頻裏學到的：
https://www.bilibili.com/video/av70711015?p=10
類似於Linux內核中的鏈表，不過是單向鏈表，並且把用於鏈接的節點放在首部

數據結構及接口(Improved_Header_List.h)

#ifndef IMPROVED_HEADER_LIST_H_INCLUDED
#define IMPROVED_HEADER_LIST_H_INCLUDED

/*注意：
在編寫鏈表時，我們並不考慮數據的內存申請釋放問題。
用戶使用時數據定義在棧上或堆上。
如果必須在鏈表內考慮釋放問題，那麼可以對函數RemoveByPos
和 Destroy進行改寫，添加參數，讓用戶傳參作爲標識
來決定是否釋放內存

如不懂可參考:
https://www.bilibili.com/video/av70711015?p=13
從6:45開始觀看
*/

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

typedef struct Node{
    struct Node *next;
}Node;

typedef struct HeaderList{
    Node head;
    int Hsize;
}HeaderList;

typedef void(*PRINTNODE)(Node*);

HeaderList* Create_HeaderList(void);
void Destroy_HeaderList(HeaderList* hlist);

void InsertByPos_HeaderList(HeaderList *hlist,int pos,Node *data);
void RemoveByPos_HeaderList(HeaderList *hlist,int pos);
void Clear_HeaderList(HeaderList *hlist);
Node* GetByPos_HeaderList(HeaderList *hlist,int pos);  // 不存在時有可能返回NULL
int GetSize_HeaderList(HeaderList *hlist);
void Print_HeaderList(HeaderList *hlist,PRINTNODE print);

#endif // IMPROVED_HEADER_LIST_H_INCLUDED

功能實現(Improved_Header_List.c)

#include "Improved_Header_List.h"

HeaderList* Create_HeaderList(void){
    HeaderList *hlist = (HeaderList*)malloc(sizeof(HeaderList));
    hlist->head.next = NULL;
    hlist->Hsize = 0;

    return hlist;
}

void Destroy_HeaderList(HeaderList* hlist){ //TODO:Check it
    if(hlist == NULL){
        fprintf(stderr,"The list doesn't exist,can't Destroy it!\n");
        return;
    }
    free(hlist);
}

void InsertByPos_HeaderList(HeaderList *hlist,int pos,Node *data){

    if(hlist == NULL){
        fprintf(stderr,"The list doesn't exist,can't InsertByPos!\n");
        return;
    }

    if(pos<=0 || pos>hlist->Hsize){
        pos = hlist->Hsize;         //友好處理
    }

    Node *prev = &(hlist->head);
    for(int i=0;i<pos;i++)
        prev = prev->next;

    Node *back = prev->next;
    prev->next = data;
    data->next = back;

    hlist->Hsize ++;
}


void RemoveByPos_HeaderList(HeaderList *hlist,int pos){

    if(hlist == NULL){
        fprintf(stderr,"The list does NOT EXIST,can't RemoveByPos!\n");
        return;
    }

    if(pos<=0 || pos>hlist->Hsize-1){
        fprintf(stderr,"The pos is INVALID,can't RemoveByPos!\n");
        return;
    }

    Node *prev = &(hlist->head);
    for(int i=0;i<pos;i++)
        prev = prev->next;

    Node *back = prev->next->next;
    prev->next = back;
    /*不銷燬出鏈表的數據，若用堆需要自行
    對數據進行內存管理*/

    hlist->Hsize --;
}

void Clear_HeaderList(HeaderList *hlist){

    if(hlist == NULL){
        fprintf(stderr,"The list does NOT EXIST,can't Clear it!\n");
        return;
    }
    if(hlist->Hsize == 0){
        fprintf(stderr,"The list is EMPTY,can't Clear it!\n");
        return;
    }
    while(hlist->Hsize != 0)
        RemoveByPos_HeaderList(hlist,0);
}

Node* GetByPos_HeaderList(HeaderList *hlist,int pos){
    if(hlist == NULL){
        fprintf(stderr,"The list does NOT EXIST,can't GetByPos!\n");
        return NULL;
    }
    if(pos<0 || pos>hlist->Hsize-1){
        fprintf(stderr,"The pos is INVALID,can't GetByPos!\n");
        return NULL;
    }

    Node *p = &(hlist->head);
    for(int i=0;i<=pos;i++)
        p = p->next;

    return p;
}


int GetSize_HeaderList(HeaderList *hlist){
    if(hlist == NULL){
        fprintf(stderr,"The list does not EXIST,can't GetSize!\n");
        return 0;
    }

    return hlist->Hsize;
}


void Print_HeaderList(HeaderList *hlist,PRINTNODE print){

    if(hlist == NULL){
        fprintf(stderr,"The list does not EXIST,can't Print it!\n");
        return;
    }
    if(hlist->Hsize == 0){
        fprintf(stderr,"The list is EMPTY,can't Print it!\n");
        return ;
    }

    printf("\nThe size of the list is:%d.\n\n",hlist->Hsize);

    Node *p = &(hlist->head);
    for(int i=0;i<hlist->Hsize;i++){
        p = p->next;
        print((void*)p);
    }
    printf("\n");
}

功能測試(main.c)

#include "Improved_Header_List.h"

typedef struct DataType{
    Node node;    //用於將鏈表中的元素串起來
    int seq;
    int randNum;
}DataType;

void test_HeaderList();

void printData(Node *data){
    DataType *p = (DataType*)data;
    printf("seq:%d\trandNum:%d\n",p->seq,p->randNum);
}

int main()
{
    test_HeaderList();
    return 0;
}

void test_HeaderList(){

    DataType data[10];
    for(int i=0;i<10;i++){
        data[i].seq = i;
        data[i].randNum = rand()%50+1;
    }

    HeaderList* hlist = Create_HeaderList();
    for(int i=0;i<10;i++)
        InsertByPos_HeaderList(hlist,0,(Node*)&data[i]);
    RemoveByPos_HeaderList(hlist,11);    // Expect error
    Print_HeaderList(hlist,printData);

    printf("print data4:\n");
    Node* data4 = GetByPos_HeaderList(hlist,4);
    printData(data4);
    printf("\n");

    Destroy_HeaderList(hlist);
    hlist = NULL;
}