Longest Common Prefix

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

If there is no common prefix, return an empty string "".

 

Example 1:

Input: strs = ["flower","flow","flight"]
Output: "fl"

Example 2:

Input: strs = ["dog","racecar","car"]
Output: ""
Explanation: There is no common prefix among the input strings.

class Solution(object):

    def longestCommonPrefix(self, strs):

       

        result = ""

        strs = sorted(strs)

        for i in range(len(strs[0])):

            s = strs[0][i]  #frist alphabet

            for j in strs:

                flag = False

                if s == j[i]:

                    flag = True

                else:

                    flag = False

           

            if flag == True:

                result += s

            else:

                break

       

        return result

Runtime: 33 ms, faster than 41.26% of Python online submissions for Longest Common Prefix.

Memory Usage: 13.9 MB, less than 12.93% of Python online submissions for Longest Common Prefix.