参考的题解
🔗:链接22. 括号生成

class Solution {public List<String> generateParenthesis(int n) {List<String> result = new ArrayList<>();backtracking(n, result, 0, 0, "");return result;}private void backtracking(int n, List<String> result, int left, int right, String str) {if (right > left) {return;}if (left == n && right == n) {result.add(str);return;}if (left < n) {backtracking(n, result, left+1, right, str+"(");}if (right < left) {backtracking(n, result, left, right+1, str+")");}}
}