题目:

题解:
python
class Solution:
def wordBreak(self, s: str, wordDict: List[str]) -> bool:
import functools
@functools.lru_cache(None)
def back_track(s):
if(not s):
return True
res=False
for i in range(1,len(s)+1):
if(s[:i] in wordDict):
res=back_track(s[i:]) or res
return res
return back_track(s)