/*
public class RandomListNode {
  int label;
  RandomListNode next = null;
  RandomListNode random = null;
  RandomListNode(int label) {
    this.label = label;
  }
}
*/
public class Solution {
  public RandomListNode Clone(RandomListNode pHead)
  {
    copyNodes(pHead);
    setClonedNodes(pHead);
    return splitNodes(pHead);
  }
    //第一步，复制链表任意结点N并创建新结点N‘，再把N'链接到N的后面
   public static void copyNodes(RandomListNode head){ 
    RandomListNode temp = head;
    while(temp!=null){
     RandomListNode clonedNode = new RandomListNode(0);
     clonedNode.next = temp.next;
     clonedNode.label = temp.label;
     clonedNode.random = null;
     temp.next = clonedNode;
     temp = clonedNode.next;
    }
   }
   //第二步，设置复制出来的结点
   public static void setClonedNodes(RandomListNode head){
    RandomListNode pNode = head;
    while(pNode!=null){
     RandomListNode pCloned = pNode.next;
     if(pNode.random!=null){
      pCloned.random = pNode.random.next; 
     }
     pNode = pCloned.next;
    }
   }
   //第三步，将第二步得到的链表拆分成两个链表
   public static RandomListNode splitNodes(RandomListNode head){
    RandomListNode pNode = head;
    RandomListNode clonedHead = null;
    RandomListNode clonedNode = null;
    if(pNode!=null){
     clonedHead = pNode.next;
     clonedNode = pNode.next;
     pNode.next = clonedNode.next;
     pNode = pNode.next;
    }
    while(pNode!=null){
     clonedNode.next = pNode.next;
     clonedNode = clonedNode.next;
     pNode.next = clonedNode.next;
     pNode = pNode.next;
    }
    return clonedHead;
   }
}