实现双向循环链表

双向循环链表

本文章将展示zack实现双向循环链表的代码

// list.h
#pragma once
#include<stdio.h>
#include<stdlib.h>
#include<assert.h>
#include<stdbool.h>typedef int data_type;
typedef struct list_node
{data_type data;struct list_node* next;struct list_node* prve;
}list_node;list_node* buy_node(data_type x);void list_init(list_node** pphead);void list_print(list_node* phead);void list_push_back(list_node* phead, data_type x);void list_push_front(list_node* phead, data_type x);bool list_empty(list_node* phead);void list_pop_back(list_node* phead);void list_pop_front(list_node* phead);list_node* list_find(list_node* phead, data_type x);// 在指定位置之前插入
void list_insert(list_node* pos, data_type x);void list_erase(list_node* pos);void list_destroy(list_node** pphead);

// list.c
#define _CRT_SECURE_NO_WARNINGS 1
#include"list.h"list_node* buy_node(data_type x)
{list_node* new_node = (list_node*)malloc(sizeof(list_node));if (new_node == NULL){perror("malloc fail");exit(1);}new_node->data = x;new_node->next = new_node->prve = new_node;return new_node;
}void list_init(list_node** pphead)
{*pphead = buy_node(-1);
}void list_print(list_node* phead)
{list_node* pcur = phead->next;while (pcur != phead){printf("%d->", pcur->data);pcur = pcur->next;}printf("\n");
}void list_push_back(list_node* phead, data_type x)
{assert(phead);list_node* new_node = buy_node(x);new_node->next = phead;new_node->prve = phead->prve;phead->prve->next = new_node;phead->prve = new_node;
}void list_push_front(list_node* phead, data_type x)
{assert(phead);list_node* new_node = buy_node(x);new_node->next = phead->next;new_node->prve = phead;phead->next->prve = new_node;phead->next = new_node;
}bool list_empty(list_node* phead)
{assert(phead);return phead->next == phead;
}void list_pop_back(list_node* phead)
{list_empty(phead);assert(phead);list_node* del = phead->prve;phead->prve->prve->next = phead;phead->prve = phead->prve->prve;free(del);del = NULL;
}void list_pop_front(list_node* phead)
{list_empty(phead);assert(phead);list_node* del = phead->next;phead->next->next->prve = phead;phead->next = phead->next->next;free(del);del = NULL;
}list_node* list_find(list_node* phead, data_type x)
{list_node* pcur = phead->next;while (pcur != phead){if (pcur->data == x)return pcur;pcur = pcur->next;}return NULL;
}void list_insert(list_node* pos, data_type x)
{assert(pos);list_node* new_node = buy_node(x);new_node->next = pos;new_node->prve = pos->prve;pos->prve->next= new_node;pos->prve = new_node;
}void list_erase(list_node* pos)
{assert(pos);pos->prve->next = pos->next;pos->next->prve = pos->prve;free(pos);pos = NULL;
}void list_destroy(list_node** pphead)
{assert(pphead && *pphead);list_node* pcur = (*pphead)->next;while (pcur != *pphead){list_node* del = pcur;pcur = pcur->next;free(del);del = NULL;}free(*pphead);*pphead = NULL;pcur = NULL;
}

// test.c
#define _CRT_SECURE_NO_WARNINGS 1
#include"list.h"void list_test01()
{list_node* plist;list_init(&plist); // 这里是传哨兵位的地址，因为plist的指向发生改变list_push_back(plist, 1);list_push_back(plist, 2);list_push_back(plist, 3);list_push_back(plist, 4);list_push_back(plist, 5);list_print(plist);list_push_front(plist, 5);list_push_front(plist, 4);list_push_front(plist, 3);list_push_front(plist, 2);list_print(plist);
}void list_test02()
{list_node* plist;list_init(&plist);list_push_back(plist, 1);list_push_back(plist, 2);list_push_back(plist, 3);list_push_back(plist, 4);list_print(plist);list_pop_back(plist);list_print(plist);list_pop_back(plist);list_print(plist);list_pop_back(plist);list_print(plist);list_pop_back(plist);list_print(plist);
}void list_test03()
{list_node* plist;list_init(&plist);list_push_back(plist, 1);list_push_back(plist, 2);list_push_back(plist, 3);list_push_back(plist, 4);list_print(plist);list_pop_front(plist);list_print(plist);list_pop_front(plist);list_print(plist);list_pop_front(plist);list_print(plist);
}void list_test04()
{list_node* plist;list_init(&plist);list_push_back(plist, 1);list_push_back(plist, 2);list_push_back(plist, 3);list_push_back(plist, 4);list_print(plist);list_node* pos = list_find(plist, 1);list_insert(pos, 22);list_print(plist);pos = list_find(plist, 22);list_erase(pos);list_print(plist);list_destroy(&plist);
}
int main()
{//list_test01();//list_test02();//list_test03();list_test04();return 0;
}

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