<p>Given <code>n</code> pairs of parentheses, write a function to <em>generate all combinations of well-formed parentheses</em>.</p> <p> </p> <p><strong>Example 1:</strong></p> <pre><strong>Input:</strong> n = 3 <strong>Output:</strong> ["((()))","(()())","(())()","()(())","()()()"] </pre><p><strong>Example 2:</strong></p> <pre><strong>Input:</strong> n = 1 <strong>Output:</strong> ["()"] </pre> <p> </p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 <= n <= 8</code></li> </ul>