LeetCode-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.

跟题目http://blog.csdn.net/my_jobs/article/details/43150797一样的方式，一个是数组，一个是链表。

public ListNode mergeTwoLists(ListNode l1, ListNode l2) {        ListNode root = null, pNode = null;        while (l1 != null && l2 != null) {        if (l1.val < l2.val) {        if (root == null) {        root = l1;        pNode = root;        } else {        pNode.next = l1;        pNode = pNode.next;        }        l1 = l1.next;        } else {        if (root == null) {        root = l2;        pNode = root;        } else {        pNode.next = l2;        pNode = pNode.next;        }        l2 = l2.next;        }        }        if (l1 != null) {        if (root == null) {    root = l1;    } else {    pNode.next = l1;    }        }        if (l2 != null) {        if (root == null) {    root = l2;    } else {    pNode.next = l2;    }        }        return root;    }

特意采用了不要链表头的方式，如果采用链表头的方式，代码会简短很多。