難度：中等
1. Descriprion
78. 最長公共前綴
2. Solution
注意特殊情況：
strs = ""-
strs中有""
class Solution:
"""
@param strs: A list of strings
@return: The longest common prefix
"""
def longestCommonPrefix(self, strs):
# write your code here
if len(strs)==0:
return ""
lens = [len(word) for word in strs]
if min(lens)==0:
return ""
for i in range(min(lens)):
c = strs[0][i]
for word in strs:
if word[i]!=c:
return strs[0][:i]
return strs[0][:i+1]
