janselv

//  The MIT License (MIT)
//
//  Copyright (c) 2016 Jansel Valentin
//
//  Permission is hereby granted, free of charge, to any person obtaining a copy
//  of this software and associated documentation files (the "Software"), to deal
//  in the Software without restriction, including without limitation the rights
//  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
//  copies of the Software, and to permit persons to whom the Software is
//  furnished to do so, subject to the following conditions:

janselv

// this implementation use xor to show the capability over pointers.
// let have 4 nodes A, B, C, D with their respective `next` pointer having
// a reference to the next and previous node(which make the list double linked).
//
// the linked list is built backward(new node become head). This implementation state that.
//
// A.pxor = B.xor(null) which is B.
// B.pxor = A.xor(C) which serve us to find both A & C
// C.pxor = B.xor(D) which serve us to find both B & D
// D.pxor = C.xor(null) which point to the prev node.