Given a group of two strings, you need to find the longest uncommon subsequence of this group of two strings. The longest uncommon subsequence is defined as the longest subsequence of one of these strings and this subsequence should not be any subsequence of the other strings.

A subsequence is a sequence that can be derived from one sequence by deleting some characters without changing the order of the remaining elements. Trivially, any string is a subsequence of itself and an empty string is a subsequence of any string.

The input will be two strings, and the output needs to be the length of the longest uncommon subsequence. If the longest uncommon subsequence doesn’t exist, return -1.

Example 1:

Input: "aba", "cdc"
Output: 3
Explanation: The longest uncommon subsequence is "aba" (or "cdc"), 
because "aba" is a subsequence of "aba", 
but not a subsequence of any other strings in the group of two strings. 

给定一组两个字符串，您需要找到这组两个字符串中最长的不常见子序列。最长的不常见子序列被定义为这些字符串之一的最长子序列，并且此子序列不应该是其他字符串的任何子序列。

子序列是可以通过删除一些字符而不改变其余元素的顺序从一个序列导出的序列。平凡地说，任何字符串都是其自身的子序列，空字符串是任何字符串的子序列。

输入将是两个字符串，输出需要是最长的不常见子序列的长度。如果最长的不常见子序列不存在，则返回-1。

Note:

1. Both strings’ lengths will not exceed 100.
2. Only letters from a ~ z will appear in input strings.

两根琴弦的长度都不会超过100。 只有来自a~z的字母才会出现在输入字符串中。