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 "".
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.
Note:
All given inputs are in lowercase letters a-z.
Solutions
1. String
# Time: O(n^2)
# Space: O(n)
class Solution:
def longestCommonPrefix(self, strs: List[str]) -> str:
if not strs:
return ''
res = []
n = len(strs[0])
for i in range(n):
cur = strs[0][i]
for s in strs:
if i >= len(s) or cur != s[i]:
return ''.join(res)
res.append(cur)
return ''.join(res)
# 118/118 cases passed (44 ms)
# Your runtime beats 14.71 % of python3 submissions
# Your memory usage beats 100 % of python3 submissions (13 MB)