<p>Given <code>n</code> pairs of parentheses, write a function to <em>generate all combinations of well-formed parentheses</em>.</p>

<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>
<pre><strong>Input:</strong> n = 3
<strong>Output:</strong> ["((()))","(()())","(())()","()(())","()()()"]
</pre><p><strong class="example">Example 2:</strong></p>
<pre><strong>Input:</strong> n = 1
<strong>Output:</strong> ["()"]
</pre>
<p>&nbsp;</p>
<p><strong>Constraints:</strong></p>

<ul>
	<li><code>1 &lt;= n &lt;= 8</code></li>
</ul>

class Solution {
public:
    vector<string> generateParenthesis(int n) {
        vector<string> result;
        queue<tuple<string, int, int>> q;
        q.push({"", 0, 0});

        while (!q.empty()) {
            auto [current, open, close] = q.front();
            q.pop();
            

            if (current.length() == 2 * n) {
                result.push_back(current);
            } else {
                if (open < n) {
                    q.push({current + '(', open + 1, close});
                }
                if (close < open) {
                    q.push({current + ')', open, close + 1});
                }
            }
        }
        
        return result;
    }
};
11489