反转链表

输入一个链表，从尾到头打印链表每个节点的值。

#include <iostream>
#include <vector>
#include <stack>

using namespace std;

struct ListNode{
    ListNode(int x) : val(x), next(NULL) {}
    int val;
    struct ListNode* next;
};

class Solution {
public:
    vector<int> printListFromTailToHead(ListNode* head)
    {
        vector<int> vec ;
        stack<int> sta;
        ListNode* p = head;
        while (p != NULL){
            sta.push(p->val);
            p = p->next;
        }
        int length = sta.size();
        for (int i = 0; i < length; ++i){
            vec.push_back(sta.top());
            sta.pop();
        }
        return vec;
    }

    void createList(ListNode* pHead, vector<int>& vec)
    {
        ListNode* p = pHead;
        vector<int>::iterator iter = vec.begin();
        for (; iter != vec.end(); ++iter)
        {
            ListNode* pNewNode = new ListNode(*iter);
            p->next = pNewNode;
            p = pNewNode;
        }
    }

};

int main()
{
    int number;
    cout << "Please input number:";
    cin >> number;
    vector<int> vec ;
    cout << "Please input node val:";
    for (int i = 0; i < number; ++i)
    {
        int nodeVal;
        cin >> nodeVal;
        vec.push_back(nodeVal);
    }

    ListNode* head = new ListNode(0);
    Solution* pSolution = new Solution();
    pSolution->createList(head, vec);
    vector<int> result ;
    result = pSolution->printListFromTailToHead(head);
    for (auto& i : result)
    {
        cout << i << endl;
    }
    system("pause");
    return 0;
}

方法一：链表从尾到头输出，利用递归实现，不使用库函数直接printf输出的时候用递归比较好

链接：https://www.nowcoder.com/questionTerminal/d0267f7f55b3412ba93bd35cfa8e8035
来源：牛客网

/**
*  struct ListNode {
*        int val;
*        struct ListNode *next;
*        ListNode(int x) :
*              val(x), next(NULL) {
*        }
*  };
*/
class Solution {
public:
    vector<int> printListFromTailToHead(struct ListNode* head) {
        vector<int> value;
        if(head != NULL)
        {
            value.insert(value.begin(),head->val);
            if(head->next != NULL)
            {
                vector<int> tempVec = printListFromTailToHead(head->next);
                if(tempVec.size()>0)
                value.insert(value.begin(),tempVec.begin(),tempVec.end());  
            }         
             
        }
        return value;
    }
};

---恢复内容结束---