05_从头到尾打印链表

叁歲伎倆 2022-06-16 09:24 157阅读 0赞

> **题目：输入一个链表的头结点，从尾到头打印链表每个结点的值。**
> 
> **思路：**从头到尾遍历链表，并用一个栈存储每个结点的值，之后出栈输出值即可。

## Java版本： ##

import java.util.Stack;
    
    public class Test {
        
    
        public static class ListNode{
        
            int value;//结点的值
            ListNode nxt;//下一个节点
        }
    
        //采用栈的方式
        public static void printListInverselyUsingIteration(ListNode root){
            //创建一个栈
            Stack<ListNode> stack = new Stack<>();
            if(root == null){
                System.out.println("链表为空");
            }
            while(root != null){
                stack.push(root);
                root = root.nxt;
            }
            ListNode tmp;
            while(!stack.isEmpty()){
                tmp = stack.pop();
                System.out.print(tmp.value+" ");
            }
        }
    
        public static void creatListNode(ListNode root1,int value,ListNode root2){
            if(root1 == null){
                System.out.println("链表为空");
            }
            root1.value = value;
            root1.nxt = root2;
            System.out.print(value + " ");
        }
    
        public static void main(String[] args) {
    
            ListNode root1 = new ListNode();
            ListNode root2 = new ListNode();
            ListNode root3 = new ListNode();
            ListNode root4 = new ListNode();
            ListNode root5 = new ListNode();
            ListNode root6 = new ListNode();
    
            System.out.print("链表反转前：");
            creatListNode(root1,12,root2);
            creatListNode(root2, 4,root3);
            creatListNode(root3,14,root4);
            creatListNode(root4, 8,root5);
            creatListNode(root5, 2,root6);
            creatListNode(root6,30, null);
    
            System.out.println();
            System.out.print("链表反转后：");
            printListInverselyUsingIteration(root1);
            System.out.println();
            printListInverselyUsingIteration(null);
        }
    }

![这里写图片描述][SouthEast]

## Python版本： ##

# -*- coding: utf-8 -*-
    class ListNode:
        def __init__(self,x=None,next1=None):
            self.value = x
            self.next = next1
    
    def creatListNode(node1,value,node2):
        if node1 == None:
            print('')
        node1 = ListNode(value)
        node1.next = node2
    
    def printListFromTailToHead(ListNode):
        if ListNode.value == None:
            return
    
        List=[]
        head = ListNode
        while head:
            # 在第0个位置处插入结点，即最前面
            List.insert(0,head.value)
            head = head.next
    
        print(List)
        return 1
    
    List=[15,11,7,18,2,4,11,6]
    length = len(List)
    Node =[]
    for i in range(length):
        Node.append(ListNode(List[i]))
    
    for j in range(length):
        if (j==length-1):
            Node[j].next=None
        else:
            Node[j].next = Node[j+1]
    
    print('链表反转前：')
    print(List)
    print('链表反转后：')
    printListFromTailToHead(Node[0])

![这里写图片描述][SouthEast 1]

[SouthEast]: /images/20220616/f7221bf85f504b8e86c1fd26d7078ea7.png
[SouthEast 1]: /images/20220616/74c77917ee7e43afb855e4a07816f9b6.png