Longest Common Prefix

Problem Description

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 "".

Examples

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.

Constraints

• 1 <= strs.length <= 200
• 0 <= strs[i].length <= 200
• strs[i] consists of only lowercase English letters if it is non-empty.

Code Template

class Solution:
    def longestCommonPrefix(self, strs: List[str]) -> str:
        # Write your code here
        pass

Solutions

• Solution 1: This approach compares characters at each position across all strings until a mismatch is found or the shortest string ends. It has a time complexity of O(N * M) and space complexity of O(1).

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