521. Longest Uncommon Subsequence I

521. Longest Uncommon Subsequence I

这是什么题，excuse me ?

class Solution(object):
    def findLUSlength(self, a, b):
        """
        :type a: str
        :type b: str
        :rtype: int
        """
        if a == b:
            return -1
        else:
            return max(len(a),len(b))

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522. Longest Uncommon Subsequence II

522. Longest Uncommon Subsequence II

刚开始没有看懂题，Subsequence是可以删掉中间的字符，所以要用两个指针，看看是不是能指向最后，优化就是把输入按照长度进行了一个排序，这样找到的第一个就是结果。

class Solution(object):
    def findLUSlength(self, strs):
        """
        :type strs: List[str]
        :rtype: int
        """
        strs.sort(key=lambda x:len(x), reverse=True)
        for i in range(len(strs)):
            count = len(strs) - 1
            for j in range(len(strs)):
                if i == j: continue
                if self.help(strs[i], strs[j])==False:
                    count -= 1
            if count == 0:
                return len(strs[I])
        return -1
    
    def help(self, s1, s2):
        if len(s1) > len(s2):
            return False
        if s1 == s2:
            return True
        i = j = 0
        while i < len(s1) and j < len(s2):
            if s1[i] == s2[j]:
                i += 1
                j += 1
            else:
                j += 1
        return i == len(s1)