<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>

import math

class Solution:
    def convert(self, s: str, numRows: int) -> str:
        if len(s) == 1 or numRows == 1:
            return s
        
        arr = []
        numCols = (len(s) // (2*numRows - 2)) * (numRows - 1)
        if len(s) % (2*numRows - 2) <= numRows:
            numCols += 1
        else:
            numCols += 1 + len(s) % (2*numRows - 2) - numRows
        # print(numCols)
        
        for _ in range(numRows):
            arr.append([""]*numCols)
        # print(arr)

        idx = 0
        for c in range(numCols):
            rem = c % (numRows - 1)
            if rem == 0:
                for r in range(numRows):
                    if idx >= len(s):
                        break
                    arr[r][c] = s[idx]
                    idx += 1
            else:
                if idx >= len(s):
                    break
                arr[numRows - rem - 1][c] = s[idx]
                idx += 1
        
        # print(arr)

        ans = ""
        for r in range(numRows):
            ans += "".join(arr[r])
        
        return ans


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