Longest Uncommon Subsequence I问题及解法

问题描述：

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.

示例：

Input: "aba", "cdc"Output: 3Explanation: 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. 

问题分析：

找出两个字符串最长的不相同子序列，也就是说，只要两者不相同，它们的最长非公共子序列的长度就是两者长度中最长的那一个。

过程详见代码：

class Solution {public:    int findLUSlength(string a, string b) {        if(a == b) return -1;        return max(a.length(),b.length());    }};