题解 | #合并两个排序的链表#

import java.util.*;

/*
 * public class ListNode {
 *   int val;
 *   ListNode next = null;
 *   public ListNode(int val) {
 *     this.val = val;
 *   }
 * }
 */

public class Solution {
    /**
     * 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
     *
     * 
     * @param pHead1 ListNode类 
     * @param pHead2 ListNode类 
     * @return ListNode类
     */
    public ListNode Merge (ListNode pHead1, ListNode pHead2) {
        ListNode fakeHead = new ListNode(-1);
    ListNode cur = fakeHead;
    while(null != pHead1 && null != pHead2) {
      if (pHead1.val < pHead2.val) {
        cur.next = pHead1;
        pHead1 = pHead1.next;
      } else {
        cur.next = pHead2;
        pHead2 = pHead2.next;
      }
      cur = cur.next;
    }

    if (null != pHead1) {
      cur.next = pHead1;
    }

    if (null != pHead2) {
      cur.next = pHead2;
    }

    return fakeHead.next;
    }
}

创建新的 list node ，然后不断二选一，添加到后面。