原题地址：https://oj.leetcode.com/problems/longest-common-prefix/

题意：Write a function to find the longest common prefix string amongst an array of strings.

解题思路：找出所有字符串共同的前缀。

代码：

class Solution:    # @return a string    def longestCommonPrefix(self, strs):        if len( strs ) == 0:            return ''        if len( strs ) == 1:            return strs[0]        minstrslen = 9999        index = 0        for i in range( 0, len( strs ) ):            if len( strs[i] ) < minstrslen:                minstrslen = len( strs[i] )                index = i        ShortestString = strs[index]        list = [0 for i in range( len( ShortestString ) )]        for i in range(0, len( ShortestString )):            for j in range(0, len( strs )):                if strs[j][i] == ShortestString[i]:                    list[i] += 1        Prefix = ''        for i in range(0, len( ShortestString )):            if list[i] == len( strs ):                Prefix += ShortestString[i]            else:                break        return Prefix