题解 | #括号生成#

package main

/**
 *
 * @param n int整型
 * @return string字符串一维数组
 */
func generateParenthesis(n int) []string {
	ans := make([]string, 0)
	var dfs func(pos int, n int, m int, vis []int)
	dfs = func(pos int, n int, m int, vis []int) {
		m++
		if pos == n-1 {
			vis[pos] = m
			arr := make([]byte, 0)
			for i := 0; i < n; i++ {
				arr = append(arr, '(')
				for j := 0; j < vis[i]; j++ {
					arr = append(arr, ')')
				}
			}
			ans = append(ans, string(arr))
			return
		}
		for i := 0; i <= m; i++ {
			vis[pos] = i
			dfs(pos+1, n, m-i, vis)
			vis[pos] = 0
		}
	}
	dfs(0, n, 0, make([]int, n))
	return ans
	// write code here
}