Data-Structures/LinkedLists/ReverseLinkedList.java at master · sb255/Data-Structures · GitHub

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/*-- Reversing a LinkedList using Stack --*/

import java.util.*;

public class ReverseLinkedList {

    static Node reverseLinkedList(Node head) {

        Stack<Integer> stack = new Stack<>();

        Node n = head;

        while(n!=null){
            stack.push(n.data);
            n = n.next;
        }

        Node newList = new Node(stack.pop());
        Node nodesNewList = newList;

        while(!stack.isEmpty()){
            nodesNewList.next = new Node(stack.pop());
            nodesNewList = nodesNewList.next;
        }

        return newList;

    }

    /*-- Inputs from the main method --*/

    public static void main(String[] args){

        Node A = new Node(5);
        A.addNodeToTail(10);
        A.addNodeToTail(20);
        A.addNodeToTail(30);
        A.addNodeToTail(35);
        A.addNodeToTail(40);
        A.addNodeToTail(50);

        Node C = reverseLinkedList(A);

        while(C!=null){
            System.out.println(C.data);
            C = C.next;
        }

    }

}

/*-- Node class Implementation --*/

class Node{

    int data;
    Node next;

    public Node(int data){
    this.data = data;
    }

    public void addNodeToTail(int addData){

        Node current = this;

        while(current!=null){

            if(current.next==null){
                current.next = new Node(addData);
                break;
            }

            current = current.next;
        }

    }

}