递归操作链表

　　C:

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

struct Node {
    int val;
    struct Node * next;
};

void CreateList(struct Node ** head) {
    int v;
    if(scanf("%d", &v)) {
        *head = (struct Node*)malloc(sizeof(struct Node));
        (*head)->val = v;
        (*head)->next = NULL;
        CreateList(&(*head)->next);
    }
}

void PositivePrint(struct Node * head) {
    if (head) {
        printf("%d ", head->val);
        PositivePrint(head->next);
    }
}

void InversePrint(struct Node * head) {
    if (head) {
        InversePrint(head->next);
        printf("%d ", head->val);
    }
}

void Destory(struct Node ** head) {
    if (*head) {
        Destory(&(*head)->next);
        free(*head);
    }
}

int main()
{
    Node * head;

    CreateList(&head);
    PositivePrint(head);
    InversePrint(head);
    Destory(&head);

    return 0;
}

　　C++:

#include <iostream>

struct Node {
    int val;
    Node * next;
    Node() {}
    Node(int v) : val(v), next(NULL) {}
    ~Node() { delete next; }
};

void CreateList(Node * & head) {
    int v;
    if(std::cin >> v) {
        head = new Node(v);
        CreateList(head->next);
    }
}

void PositiveShow(Node * head) {
    if(head) {
        std::cout << head->val << ' ';
        PositiveShow(head->next);
    }
}

void InverseShow(Node * head) {
    if(head) {
        InverseShow(head->next);
        std::cout << head->val << ' ';
    }
}

int main()
{
    Node * head;

    CreateList(head);
    PositiveShow(head);
    InverseShow(head);

    return 0;
}