Leetcode 139. Word Break. Python

139. Word Break

Given a string s and a dictionary of strings wordDict, return true if s can be segmented into a space-separated sequence of one or more dictionary words.

Note that the same word in the dictionary may be reused multiple times in the segmentation.

Example :

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

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

Explaination :

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