LeetCode Online Judge 题目C# 练习 - 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.

public static ListNode MergeTwoSortedLists(ListNode A, ListNode B)
{
if (A == null)
return B;
if (B == null)
return A;

ListNode ret;
ListNode curr;

if (A.val <= B.val)
{
ret = A;
A = A.next;
}
else
{
ret = B;
B = B.next;
}

curr = ret;

while (A != null || B != null)
{
if (A == null)
{
curr.next = B;
B = B.next;
curr = curr.next;
continue;
}
if (B == null)
{
curr.next = A;
A = A.next;
curr = curr.next;
continue;
}
if (A.val <= B.val)
{
curr.next = A;
A = A.next;
curr = curr.next;
continue;
}
else
{
curr.next = B;
B = B.next;
curr = curr.next;
continue;
}
}

return ret;
}

代码分析：

　　最最基本的题了，什么都没考。。。BF,O(n).