word break solution

Author: devyejin

word-break/devyejin.py

@@ -0,0 +1,24 @@
+from typing import List
+
+
+class Solution:
+    def wordBreak(self, s: str, wordDict: List[str]) -> bool:
+        def dfs(subs: str):
+            if subs in memo:
+                return memo[subs]
+
+            if not subs:
+                return True
+
+            for word in wordDict:
+                if subs.startswith(word):
+                    if dfs(subs[len(word):]):
+                        memo[subs] = True
+                        return True
+
+            memo[subs] = False
+            return False
+
+        memo = {}
+        return dfs(s)
+