leetcode_gym/_problems/longestCommonPrefix.md

layout, title, last_solved, category, leetcode_url, status

layout	title	last_solved	category	leetcode_url	status
page	Longest Common Prefix	2020-06-05	string	https://leetcode.com/problems/longest-common-prefix	Solved

Problem

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: ["flower","flow","flight"]
Output: "fl"
Example 2:

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

Solution

{% highlight python %}

def lcp(strs):

prefix = strs[0]

for i in range(1, len(strs)):

    # if substring is found, it will return the first index
    # if that element isn't the first char, then chop off
    while strs[i].find(prefix) != 0:

        # keep chopping off the last character
        prefix = prefix[0: len(prefix)-1]
        if not prefix: return ""
    
return prefix

{% endhighlight %}