1 files changed, 40 insertions, 0 deletions
diff --git a/1239/main.py b/1239/main.py
new file mode 100755
index 0000000..0ef5ef1
--- /dev/null
+++ b/1239/main.py
@@ -0,0 +1,40 @@
+#!/usr/bin/env python
+
+
+import typing
+
+
+class Solution:
+    def maxLength(self, arr: typing.List[str]) -> int:
+        result = [0]
+        self.dfs(arr, "", 0, result)
+        return result[0]
+
+    def dfs(self, arr, path, idx, result):
+        if self.isUniqueChars(path):
+            result[0] = max(result[0], len(path))
+
+        if idx == len(arr) or not self.isUniqueChars(path):
+            return
+
+        for i in range(idx, len(arr)):
+            self.dfs(arr, path + arr[i], i + 1, result)
+
+    def isUniqueChars(self, s):
+        char_set = set()
+        for c in s:
+            if c in char_set:
+                return False
+            char_set.add(c)
+        return True
+
+
+def main():
+    solution = Solution()
+    print(solution.maxLength(["un", "iq", "ue"]))
+    print(solution.maxLength(["cha", "r", "act", "ers"]))
+    print(solution.maxLength(["abcdefghijklmnopqrstuvwxyz"]))
+
+
+if __name__ == "__main__":
+    main()