@author jackzhenguo
@desc
@date 2019/9/4
101 str1是否由str2旋转而来
stringbook旋转后得到bookstring,写一段代码验证str1是否为str2旋转得到。
思路
转化为判断：str1是否为str2+str2的子串
def is_rotation(s1: str, s2: str) -> bool:
if s1 is None or s2 is None:
return False
if len(s1) != len(s2):
return False
def is_substring(s1: str, s2: str) -> bool:
return s1 in s2
return is_substring(s1, s2 + s2)
测试
r = is_rotation('stringbook', 'bookstring')
print(r) # True
r = is_rotation('greatman', 'maneatgr')
print(r) # False
