LeetCode 22 括号生成

Posted 2022-06-14 Starzkg

https://leetcode-cn.com/problems/generate-parentheses/

解决方案

class Solution 
    List<String> ans = new ArrayList<>();

    public List<String> generateParenthesis(int n) 
        dfs("", 0, n);
        return ans;
    

    public void dfs(String s, int stack, int n) 
        if (s.length() == n * 2) 
            if (stack == 0) 
                ans.add(s);
            
            return;
        
        if (stack < n) 
            dfs(s + '(', stack + 1, n);
        
        if (stack > 0) 
            dfs(s + ')', stack - 1, n);