Copy List with Random Pointer

標籤：java   leetcode   

題目

A linked list is given such that each node contains an additional random pointer which could point to any node in the list or null.

Return a deep copy of the list.

方法

    public RandomListNode copyRandomList(RandomListNode head) {        RandomListNode newHead = null;                if (head != null) {        RandomListNode cur = head;        while (cur != null) {        RandomListNode temp = new RandomListNode(cur.label);        temp.next = cur.next;        cur.next = temp;        cur = cur.next.next;        }        cur = head;        RandomListNode newCur = head.next;        while(cur != null) {        if (cur.random != null) {        newCur.random = cur.random.next;        }        cur = cur.next.next;        if (cur != null) {        newCur = newCur.next.next;        }                }                cur = head;        newHead = cur.next;        newCur = newHead;        while (cur != null) {        cur.next = newCur.next;        cur = newCur.next;        if (cur != null) {        newCur.next = cur.next;        newCur = cur.next;        } else {        newCur.next = null;        }        }        }                        return newHead;    }