编写一个函数来查找字符串数组中的最长公共前缀。

如果不存在公共前缀，返回空字符串 ""。

示例 1:

输入: ["flower","flow","flight"]输出: "fl"

示例 2:

输入: ["dog","racecar","car"]输出: ""解释: 输入不存在公共前缀。

说明:

所有输入只包含小写字母 a-z 。

class Solution:    def longestCommonPrefix(self, strs):        """        :type strs: List[str]        :rtype: str        """        if not strs:            return ''        s1 = min(strs)        s2 = max(strs)        for i,j in  enumerate(s1):            if j != s2[i]:                return s1[:i]        return s1if __name__ == '__main__':    s=Solution()    print(s.longestCommonPrefix(["flower","flow","flight"]))