创建2个新的链表

package main
import . "nc_tools"
/*
 * type ListNode struct{
 *   Val int
 *   Next *ListNode
 * }
 */

/**
  * 
  * @param head ListNode类 
  * @param x int整型 
  * @return ListNode类
*/
func partition( head *ListNode ,  x int ) *ListNode {
    // write code here
    if head == nil {
        return head
    }

//  创建两个新的链表, 用于存储对应的节点
//  dump 存储小于x的节点
//  dump2 存储大于等于x的节点
    dump, dump2 := &ListNode{}, &ListNode{}
    p1, p2 := dump, dump2

    for curr := head; curr != nil; curr = curr.Next {
        if curr.Val >= x {
            p2.Next = curr
            p2 = curr
        }else{
            p1.Next = curr
            p1 = curr
        }
    }

    p1.Next = dump2.Next
    p2.Next = nil

    return dump.Next
}