C语言数据结构学习——双向链表

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

typedef struct DoubleLinkTable{
    struct DoubleLinkTable * prior;
    int data;
    struct DoubleLinkTable * next;
}DoubleLinkTable;

/**
 * @brief 
 * init double link list
 * @param head 
 * @return DoubleLinkTable* 
 */
DoubleLinkTable* initDoubleLinkTable(DoubleLinkTable * head){
    head = (DoubleLinkTable*)malloc(sizeof(DoubleLinkTable));
    head->prior = NULL;
    head->next = NULL;
    head->data = 0;
    DoubleLinkTable * list = head;
    for(int i = 1;i <= 5; i ++){
        DoubleLinkTable * body = (DoubleLinkTable*)malloc(sizeof(DoubleLinkTable));
        body->prior = NULL;
        body->next = NULL;
        body->data = i;

        list->next = body;
        body->prior = list;
        list = list->next;
    }
    return head;
}

/**
 * @brief 
 * insert a element into table
 * @param head      source table
 * @param data      element data
 * @param add       target site
 * @return DoubleLinkTable* 
 */
DoubleLinkTable * insertDoubleLinkTable(DoubleLinkTable * head, int data, int add){
    DoubleLinkTable * temp = (DoubleLinkTable*)malloc(sizeof(DoubleLinkTable));
    temp->data = data;
    temp->prior = NULL;
    temp->next = NULL;
    if(add == 1){
        temp->next = head;
        head->prior = temp;
        head = temp;
    }else{
        DoubleLinkTable * body = head;
        for(int i = 1; i < add - 1; i ++){
            body = body->next;
        }
        if(body->next == NULL){
            body->next = temp;
            temp->prior = body;
        }else{
            body->next->prior = temp;
            temp->next = body->next;
            body->next = temp;
            temp->prior = body;
        }
    }
    return head;
}

/**
 * @brief 
 * delete a element which same as give
 * @param head      source data
 * @param data      target data
 * @return DoubleLinkTable* 
 */
DoubleLinkTable * deleteDoubleLinkTable(DoubleLinkTable * head, int data){
    DoubleLinkTable * temp = head;
    while (temp){
        if(temp->data == data){
            temp->prior->next = temp->next;
            temp->next->prior = temp->prior;
            free(temp);
            return head;
        }
        temp = temp->next;
    }
    printf("double link table not have the element");
    return head;
    
}

int selectElement(DoubleLinkTable * head, int element){
    DoubleLinkTable * t = head;
    int i = 1;
    while(t){
        if(t->data == element){
            return i;
        }
        i ++;
        t = t->next;
    }
    return -1;
}

DoubleLinkTable *amendElement(DoubleLinkTable * p, int add, int newElement){
    DoubleLinkTable * temp = p;
    for(int i = 1; i < add; i ++){
        temp = temp->next;
    }
    temp->data = newElement;
    return p;
}

void display(DoubleLinkTable * head){
    DoubleLinkTable * temp = head;
    while(temp){
        if(temp->next == NULL){
            printf("%d\n", temp->data);
        }else{
            printf("%d->", temp->data);
        }
        temp = temp->next;
    }
}

int main(){
    DoubleLinkTable * head = NULL;
    head = initDoubleLinkTable(head);
    display(head);

    head = insertDoubleLinkTable(head, 7, 3);
    display(head);

    head = deleteDoubleLinkTable(head, 2);
    display(head);

    int targetElement = selectElement(head, 3);
    printf("element 3`s site is:%d\n", targetElement);

    head = amendElement(head, 3, 6);
    display(head);
    return 0;
}