Java for LeetCode 021 Merge Two Sorted Lists

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.

解题思路：

新建一个ListNode进行存储即可，JAVA实现如下：

	static public ListNode mergeTwoLists(ListNode l1, ListNode l2) {
		ListNode listnode=new ListNode(0);
		ListNode index=listnode;
		while(l1!=null&&l2!=null){
			if(l1.val>l2.val){
				ListNode temp=l1;
				l1=l2;
				l2=temp;
			}
			index.next=new ListNode(l1.val);
			index=index.next;
			l1=l1.next;
		}
		if(l1==null)
			index.next=l2;
		else
			index.next=l1;
		return listnode.next;
	}