<p>The string <code>&quot;PAYPALISHIRING&quot;</code> is written in a zigzag pattern on a given number of rows like this: (you may want to display this pattern in a fixed font for better legibility)</p>

<pre>
P   A   H   N
A P L S I I G
Y   I   R
</pre>

<p>And then read line by line: <code>&quot;PAHNAPLSIIGYIR&quot;</code></p>

<p>Write the code that will take a string and make this conversion given a number of rows:</p>

<pre>
string convert(string s, int numRows);
</pre>

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

<pre>
<strong>Input:</strong> s = &quot;PAYPALISHIRING&quot;, numRows = 3
<strong>Output:</strong> &quot;PAHNAPLSIIGYIR&quot;
</pre>

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

<pre>
<strong>Input:</strong> s = &quot;PAYPALISHIRING&quot;, numRows = 4
<strong>Output:</strong> &quot;PINALSIGYAHRPI&quot;
<strong>Explanation:</strong>
P     I    N
A   L S  I G
Y A   H R
P     I
</pre>

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

<pre>
<strong>Input:</strong> s = &quot;A&quot;, numRows = 1
<strong>Output:</strong> &quot;A&quot;
</pre>

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

<ul>
	<li><code>1 &lt;= s.length &lt;= 1000</code></li>
	<li><code>s</code> consists of English letters (lower-case and upper-case), <code>&#39;,&#39;</code> and <code>&#39;.&#39;</code>.</li>
	<li><code>1 &lt;= numRows &lt;= 1000</code></li>
</ul>

class Solution {
public:
     std::string convert(std::string s, int numRows) {
        if(numRows < 2) return s;
    int i = 0;
    std::string res{};
    //int arrSize = s.size() % numRows > 0 ? s.size() / numRows + 1 : s.size() / numRows;
    std::vector<std::vector<char>> arr;
    arr.reserve(numRows);
    int j = 0;
    for (; j < numRows&& i < s.length(); ++j, ++i) {
        arr.push_back({s[i]});
    }
    while (i < s.size()) {
        for(j = j = arr.size() - 2; j > 0&& i < s.length(); --j) {
            arr[j].push_back(s[i++]);

        }
        for(; j < numRows&& i < s.length(); ++j) {
            arr[j].push_back(s[i++]);
        }
        /*for(j = j - 2; j > 0&& i < s.length(); --j) {
            arr[j].push_back(s[i++]);

        }*/
        //--j;
    }
    for (auto arr1 : arr) {
        for (auto arr2 : arr1) {
            res += arr2;
        }
    }
    return res;
}
};
19193