Word Break

[huimeich]

Given a non-empty string s and a dictionary wordDict containing a list of non-empty words, determine if s can be segmented into a space-separated sequence of one or more dictionary words.

Note:

The same word in the dictionary may be reused multiple times in the segmentation. You may assume the dictionary does not contain duplicate words. Example 1:

Input: s = "leetcode", wordDict = ["leet", "code"] Output: true Explanation: Return true because "leetcode" can be segmented as "leet code". Example 2:

Input: s = "applepenapple", wordDict = ["apple", "pen"] Output: true Explanation: Return true because "applepenapple" can be segmented as "apple pen apple". Note that you are allowed to reuse a dictionary word. Example 3:

Input: s = "catsandog", wordDict = ["cats", "dog", "sand", "and", "cat"] Output: false

[huimeich]

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