问题描述：

Merge two sorted linked lists and return it as a new list. The new list should be made by splicing together the nodes of the first two lists.

代码：

import java.util.List;


public class Merge_Two_Sorted_Lists {  //java

	  public class ListNode {
	      int val;
	      ListNode next;
	      ListNode(int x) {
	          val = x;
	          next = null;
	      }
	  }
	 
	
    public ListNode mergeTwoLists(ListNode l1, ListNode l2) {
        if(l2 == null)
        	return l1;
        if(l1 == null)
        	return l2;
        
        ListNode tmp1 = l1;
        ListNode tmp2 = l2;
        ListNode head = new ListNode(0);
        ListNode result = head;
        while(tmp1 != null && tmp2 != null){
        	if(tmp1.val > tmp2.val){
        		ListNode node = new ListNode(tmp2.val);
        		result.next = node;
        		result = result.next;
        		tmp2 = tmp2.next;
        	}
        	
        	else{
        		ListNode node = new ListNode(tmp1.val);
        		result.next = node;
        		result = result.next;
        		tmp1 = tmp1.next;
        	}
        }
        
        if(tmp2 == null)
        	result.next = tmp1;
        else result.next = tmp2;
        
        return head.next;
        	
    }

}

[leetcode]Merge Two Sorted Lists