lc139.单词拆分

class Solution:
    def wordBreak(self, s: str, wordDict: List[str]) -> bool:
        size = len(s)
        dp = [False]*(size+1)
        dp[0] = True
        for i in range(size):
            for j in range(i+1, size+1):
                if dp[i] and s[i:j] in wordDict:
                    dp[j] = True
        return dp[-1]