单链表（双指针）

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

typedef struct Node{
    int value;
    struct Node *pNext;
} Node;

/* 打印链表 */
void show_data(Node *head) {
    if (head == NULL) {
        return;
    }
    Node* cur = head;
    while (cur) {
        printf("%d ", cur->value);
        cur = cur->pNext;
    }
    printf("\n");
}

/* 创建链表 */
Node* creatNode_New(int data) {
    Node* new = (Node*)malloc(sizeof(Node));
    new->value = data;
    new->pNext = NULL;
    return new;
}

/* 反转链表 */
Node* revertNode(Node* head) {
    Node* cur = head;
    Node* next = NULL;

    while (cur != NULL) {
        Node* tmp = cur;
        cur = cur->pNext;
        tmp->pNext = next;
        next = tmp;
    }
    return next;
}

/* 插入链表_表头 */
void insertNode_Front(Node** head, Node* new) {
    if (head == NULL) {
        *head = new;
    }
    else {
        new->pNext = *head;
        *head = new;
    }
}

/* 插入链表_表尾 */
void insertNode_Back(Node** head, Node* new) {
    if (head == NULL) {
        *head = new;
    }
    else {
        Node* tmp = *head;
        while (tmp->pNext != NULL) {
            tmp = tmp->pNext;
        }
        tmp->pNext = new;
    }
}

/* 统计链表长度 */
int GetNodeSize(Node* head) {
    if (head == NULL) {
        return 0;
    }
    int size = 0;
    Node* cur = head;

    while (cur) {
        size++;
        cur = cur->pNext;
    }
    printf("size:%d\n", size);
    return size;
}

/* 删除链表_表头 */
void deleteNode_Front(Node** head) {
    if (*head == NULL) {
        return;
    }
    else {
        if ((*head)->pNext == NULL) {
            free(*head);
            *head = NULL;
        }
        else {
            Node* cur = *head;
            *head = (*head)->pNext;
            free(cur);
        }
    }
}

/* 删除链表_表尾 */
void deleteNode_Back(Node** head) {
    if (*head == NULL) {
        return;
    }
    else {
        if ((*head)->pNext == NULL) {
            free(*head);
            *head = NULL;
        }
        else {
            Node* cur = *head;
            Node* pre = NULL;
            while (cur->pNext) {
                pre = cur;
                cur = cur->pNext;
            }
            free(cur);
            pre->pNext = NULL;
        }
    }
}

/* 清空链表 */
void cleanNodeList(Node** head) {
    Node* cur = *head;
    while (cur) {
        Node* tmp = cur;
        cur = cur->pNext;
        free(tmp);
    }
    *head = NULL;
}

int main(void) {
    Node* head = NULL;
    Node* revNode = NULL;
    for (int i = 1; i < 10; i++) {
        insertNode_Front(&head, creatNode_New(i));
    }
    GetNodeSize(head);
    show_data(head);
    revNode = revertNode(head);
    show_data(revNode);
    deleteNode_Front(&revNode);
    show_data(revNode);
    deleteNode_Back(&revNode);
    show_data(revNode);
    cleanNodeList(&revNode);
    show_data(revNode);

    return 0;
}