Leetcode - Longest Common Prefix Solution

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.


  • 0 <= strs.length <= 200
  • 0 <= strs[i].length <= 200
  • strs[i] consists of only lower-case English letters.

Solution in Python

class Solution:
    def longestCommonPrefix(self, strs: List[str]) -> str:
        common_prefix = ""
        if not strs:
            return common_prefix
        shortest_len = min(map(len,strs))
        for i in range(shortest_len):
            current_letter = strs[0][i] 
            for word in strs:
                if word[i]!= current_letter:
                    return common_prefix
        return common_prefix

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