編寫一個函數(shù)來查找字符串數(shù)組中的最長公共前綴。
如果不存在公共前綴，返回空字符串 ""
所有輸入只包含小寫字母 a-z

1、

class Solution(object):
    def longestCommonPrefix(self, strs):
        if not strs:
            return ""
        for i in range(len(strs[0])):
            for string in strs[1:]:
                if i >= len(string) or strs[0][i] != string[i]:
                    return strs[0][:i]
        # 特殊情況[""]有一個為空元素
        return strs[0]

2、利用集合去重的原理

class Solution(object):
    def longestCommonPrefix(self, strs):
        result = ""
        i = 0
        while True:
            try:
                sets = set(string[i] for string in strs)
                if len(sets)==1:
                    result += sets.pop()
                    i += 1
                else:
                    break
            except Exception as e:
                break
        return result