<p>You are given an alphanumeric string <code>s</code>. (<strong>Alphanumeric string</strong> is a string consisting of lowercase English letters and digits).</p>

<p>You have to find a permutation of the string where no letter is followed by another letter and no digit is followed by another digit. That is, no two adjacent characters have the same type.</p>

<p>Return <em>the reformatted string</em> or return <strong>an empty string</strong> if it is impossible to reformat the string.</p>

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

<pre>
<strong>Input:</strong> s = &quot;a0b1c2&quot;
<strong>Output:</strong> &quot;0a1b2c&quot;
<strong>Explanation:</strong> No two adjacent characters have the same type in &quot;0a1b2c&quot;. &quot;a0b1c2&quot;, &quot;0a1b2c&quot;, &quot;0c2a1b&quot; are also valid permutations.
</pre>

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

<pre>
<strong>Input:</strong> s = &quot;leetcode&quot;
<strong>Output:</strong> &quot;&quot;
<strong>Explanation:</strong> &quot;leetcode&quot; has only characters so we cannot separate them by digits.
</pre>

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

<pre>
<strong>Input:</strong> s = &quot;1229857369&quot;
<strong>Output:</strong> &quot;&quot;
<strong>Explanation:</strong> &quot;1229857369&quot; has only digits so we cannot separate them by characters.
</pre>

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

<ul>
	<li><code>1 &lt;= s.length &lt;= 500</code></li>
	<li><code>s</code> consists of only lowercase English letters and/or digits.</li>
</ul>

class Solution {
public:
    string reformat(string s) {
        int digits = 0;
        int symbols = 0;
        string temp = s;
        string result;
        for (int i = 0; i < s.size(); ++i) {
            if (isdigit(s[i])) {
                ++digits;
            }
            else {
                ++symbols;
            }
        }
        if (symbols - digits > 1 || symbols - digits < -1)
        {
            
            return result;
        }
        std::sort(temp.begin(), temp.end());
        int j = 0, x = 0;
        int i = (symbols >= digits ? 0 : 1);
        for (i; i < temp.size() + (symbols >= digits ? 0 : 1); ++i) {
            if ((i + 1) % 2 == 0) {
                result.push_back(temp[x]);
                ++x;
            }
            else {
                result.push_back(*(temp.rbegin() + j));
                ++j;
            }
        }
        return result;
    }
};
9200