<p>You are given a string <code>s</code> that consists of lower case English letters and brackets.</p>

<p>Reverse the strings in each pair of matching parentheses, starting from the innermost one.</p>

<p>Your result should <strong>not</strong> contain any brackets.</p>

<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>

<pre>
<strong>Input:</strong> s = &quot;(abcd)&quot;
<strong>Output:</strong> &quot;dcba&quot;
</pre>

<p><strong class="example">Example 2:</strong></p>

<pre>
<strong>Input:</strong> s = &quot;(u(love)i)&quot;
<strong>Output:</strong> &quot;iloveu&quot;
<strong>Explanation:</strong> The substring &quot;love&quot; is reversed first, then the whole string is reversed.
</pre>

<p><strong class="example">Example 3:</strong></p>

<pre>
<strong>Input:</strong> s = &quot;(ed(et(oc))el)&quot;
<strong>Output:</strong> &quot;leetcode&quot;
<strong>Explanation:</strong> First, we reverse the substring &quot;oc&quot;, then &quot;etco&quot;, and finally, the whole string.
</pre>

<p>&nbsp;</p>
<p><strong>Constraints:</strong></p>

<ul>
	<li><code>1 &lt;= s.length &lt;= 2000</code></li>
	<li><code>s</code> only contains lower case English characters and parentheses.</li>
	<li>It is guaranteed that all parentheses are balanced.</li>
</ul>

class Solution {
public:
    string reverseParentheses(string s) {
        stack<int> parentheses;
        unordered_map<int, int> teleportTable;
        for (int i = 0 ; i < s.size() ; i++)
        {
            if (s[i] == '(')
                parentheses.push(i);
            else if (s[i] == ')')
            {
                int front = parentheses.top();
                parentheses.pop();

                teleportTable[front] = i;
                teleportTable[i] = front;
            }
        }

        string result;
        
        for (int i = 0, direction = 1 ; i < s.size() ; i = i + direction)
        {
            if (s[i] == '(' || s[i] == ')')
            {
                i = teleportTable[i];
                direction = direction * -1;
            }
            else
            {
                result = result + s[i];
            }
        }

        return result;
    }
};
10800