Leetcode 22. Generate Parentheses

You are given an integer n. Return all well-formed parentheses strings that you can generate with n pairs of parentheses.

Examples

Example 1

Input:  n = 1
Output: ["()"]

Example 2

Input:  n = 3
Output: ["((()))","(()())","(())()","()(())","()()()"]

Constraints

• 1 <= n <= 7