<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:
    def convert(self, s: str, numRows: int) -> str:
        a = s
        rows = numRows
        lst=list(a)
        mlst=[]
        l1=[]
        l4=[]
        l2=[]
        l5=[]
        l3=[]
        def recur(lst,rows):
    
            for i in range(0,len(lst),2*(rows)-2):
                l2.append(lst[i])
                l1.append(i)
        
            for i in range(rows-1,len(lst),2*rows-2):
                l3.append(lst[i])
                l1.append(i)
            for i in range(len(lst)):
                if i not in l1:
                    l4.append(lst[i])
            mlst.append(''.join(l2))
            now(l4,rows-2)
            mlst.append(''.join(l3))
            return (''.join(mlst))
        def now(lst,rows):
            if len(lst)>0:
                l5=[]
                l6=[0]
                l7=[]
                l5.append(lst[0])
                i=2*rows-1
                while(i<=len(lst)-1 and i!=0):
                    if i == len(lst)-1:
                        l5.append(lst[i])
                        l6.append(i)
                        break
                    l5.append(lst[i])
                    l6.append(i)
                    l5.append(lst[i+1])
                    l6.append(i+1)
                    i+=1
                    i+=2*rows-1
                for i in range(len(lst)):
                    if i not in l6:
                        l7.append(lst[i])
                mlst.append(''.join(l5))
                now(l7,rows-1)
        if rows == 1:
            return a
        else:
            l=recur(lst,rows)
            return l


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