复杂链表的复制 -- java

请实现函数，用于复制一个复杂链表。在复杂链表中，每个结点除了有一个next指针指向下一个结点外，还有一个sibling指向链表中的任意结点或者NULL。

复杂链表如下图：

复杂节点定义如下：

public class ComplexListNode {
    int value;
    ComplexListNode next;

    public ComplexListNode() {
    }

    ComplexListNode sibling;

    public ComplexListNode(int value) {
        this.value = value;
    }
}

1. 在每个节点的后面插入复制的节点，如下图：
   
2. 对复制的节点的sibling指针进行赋值，如下图：
   
   将上面的链表拆成两个链表，原始链表和复制链表，如下图：
   

public class Clone {
    public static ComplexListNode clone(ComplexListNode head) {
        cloneNodes(head);
        connectSiblingNodes(head);
        return reconnectNodes(head);
    }

    // 复制链表节点，把复制后的节点N'放在原节点N的后面
    public static void cloneNodes(ComplexListNode head) {
        while (head != null) {
            ComplexListNode cloned = new ComplexListNode();
            cloned.value = head.value;
            cloned.next = head.next;
            cloned.sibling = null;

            head.next = cloned;

            head = cloned.next;
        }
    }

    // 设置复制出来的节点的sibling
    public static void connectSiblingNodes(ComplexListNode head) {
        while (head != null) {
            ComplexListNode cloned = head.next;
            cloned.sibling = head.sibling.next;

            head = cloned.next;
        }
    }

    // 把这个长链表拆分为两个链表
    public static ComplexListNode reconnectNodes(ComplexListNode head) {
        // 复制链表的头结点
        ComplexListNode clonedHead = null;
        // 用于临时存储复制链表的节点
        ComplexListNode clonedNode = null;

        if (head != null) {
            // 设置复制链表的头结点
            clonedHead = clonedNode = head.next;
            head.next = clonedHead.next;
            head = head.next;
        }

        while (head != null) {
            clonedNode.next = head.next;
            clonedNode = clonedNode.next;
            head.next = clonedNode.next;

            head = head.next;
        }

        return clonedHead;
    }

    // 打印，用于测试
    public static void printNodes(ComplexListNode head) {
        System.out.println("head.value" + "t" + "head.sibling.value");
        while (head != null) {
            System.out.print(head.value + "t" + "t" + "t");
            if (head.random != null) {
                System.out.print(head.random.value);
            } else {
                System.out.print("null");
            }
            System.out.println();
            head = head.next;
        }
    }

    // 测试程序
    public static void main(String[] args) {
        ComplexListNode node1 = new ComplexListNode(1);
        ComplexListNode node2 = new ComplexListNode(2);
        ComplexListNode node3 = new ComplexListNode(3);

        node1.next = node2;
        node2.next = node3;

        node1.sibling = node3;
        node2.sibling = node1;
        node3.sibling = node2;

        // 复制后的链表
        ComplexListNode cloned = clone(node1);
        printNodes(cloned);
        System.out.println();

        // 不影响原链表
        printNodes(node1);
    }
}

来自：

《剑指Offer》
Coding-Interviews/复杂链表的复制.md at master · todorex/Coding-Interviews