Create 22-Generate-Parentheses.py

javiermon · Dec 25, 2021 · 2f21f3d · 2f21f3d
1 parent ff74d3e
commit 2f21f3d
Showing 1 changed file with 21 additions and 0 deletions.
diff --git a/22-Generate-Parentheses.py b/22-Generate-Parentheses.py
@@ -0,0 +1,21 @@
+class Solution:
+ def generateParenthesis(self, n: int) -> List[str]:
+ stack = []
+ res = []
+
+ def backtrack(openN, closedN):
+ if openN == closedN == n:
+ res.append("".join(stack))
+ return
+
+ if openN < n:
+ stack.append("(")
+ backtrack(openN + 1, closedN)
+ stack.pop()
+ if closedN < openN:
+ stack.append(")")
+ backtrack(openN, closedN + 1)
+ stack.pop()
+
+ backtrack(0, 0)
+ return res