题目
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 “”.
解题思路
方法1，前两个字符串求最长公共前缀，结果和下一个字符串求，直到结束
方法2，对所有字符串排序，结果为第一和最后一个字符串的最长公共前缀
代码
class Solution:
def longestCommonPrefix(self, strs: List[str]) -> str:
def get_common_prefix(s1, s2):
if len(s1) > len(s2):
s1, s2 = s2, s1
for i in range(len(s1)):
if s1[i] != s2[i]:
return s1[:i]
return s1
if len(strs) == 0:
return ""
if len(strs) == 1:
return strs[0]
res = get_common_prefix(strs[0], strs[1])
for s in strs[2:]:
res = get_common_prefix(res, s)
return res
class Solution:
def longestCommonPrefix(self, strs: List[str]) -> str:
def get_common_prefix(s1, s2):
if len(s1) > len(s2):
s1, s2 = s2, s1
for i in range(len(s1)):
if s1[i] != s2[i]:
return s1[:i]
return s1
strs = sorted(strs)
return get_common_prefix(strs[0], strs[-1])
