[nb] Commit

dynamic-programming/22-generate-parenthesis/python/index.py

@@ -0,0 +1,25 @@
+from typing import List
+# ()()()
+# (())()
+# ((()))
+# ()(())
+# (()())
+
+def generateParenthesis(n: int) -> List[str]:
+    ans = []
+    def backtrack(S = [], left = 0, right = 0):
+        if len(S) == 2 * n:
+            ans.append("".join(S))
+            return
+        if left < n:
+            S.append("(")
+            backtrack(S, left+1, right)
+            S.pop()
+        if right < left:
+            S.append(")")
+            backtrack(S, left, right+1)
+            S.pop()
+    backtrack()
+    return ans
+
+generateParenthesis(3)