<p>Given two integers <code>a</code> and <code>b</code>, return <strong>any</strong> string <code>s</code> such that:</p>

<ul>
	<li><code>s</code> has length <code>a + b</code> and contains exactly <code>a</code> <code>&#39;a&#39;</code> letters, and exactly <code>b</code> <code>&#39;b&#39;</code> letters,</li>
	<li>The substring <code>&#39;aaa&#39;</code> does not occur in <code>s</code>, and</li>
	<li>The substring <code>&#39;bbb&#39;</code> does not occur in <code>s</code>.</li>
</ul>

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

<pre>
<strong>Input:</strong> a = 1, b = 2
<strong>Output:</strong> &quot;abb&quot;
<strong>Explanation:</strong> &quot;abb&quot;, &quot;bab&quot; and &quot;bba&quot; are all correct answers.
</pre>

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

<pre>
<strong>Input:</strong> a = 4, b = 1
<strong>Output:</strong> &quot;aabaa&quot;
</pre>

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

<ul>
	<li><code>0 &lt;= a, b &lt;= 100</code></li>
	<li>It is guaranteed such an <code>s</code> exists for the given <code>a</code> and <code>b</code>.</li>
</ul>

class Solution {
public:
    string strWithout3a3b(int a, int b) {
        std::string s;

        int l = a > b ? b : a;
        char lc = a > b ? 'b' : 'a';
        char mc = lc == 'a' ? 'b' : 'a';
        
        for (int i = 0; i < l * 2; ++i) {
            s += mc;
            s += 'x';
            s+= lc;
        }

        for (int i = 1, c = l * 2; i < s.size() && c < a + b; i += 3) {
            s[i] = mc;
            c++;
        }
        int index = 0;
        while ((index = s.find("x")) != s.npos ) {
            s.erase(index, 1);
        }

        return s.size() > a + b ? s.substr(0, a + b) : s;
    }
};
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