The string `"PAYPALISHIRING"` 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   A   H   N
    A P L S I I G
    Y   I   R

And then read line by line: `"PAHNAPLSIIGYIR"`

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

    string convert(string s, int numRows);

Example 1:

    Input: s = "PAYPALISHIRING", numRows = 3
    Output: "PAHNAPLSIIGYIR"

Example 2:

    Input: s = "PAYPALISHIRING", numRows = 4
    Output: "PINALSIGYAHRPI"
    Explanation:
    P     I    N
    A   L S  I G
    Y A   H R
    P     I

Example 3:

    Input: s = "A", numRows = 1
    Output: "A"

Constraints:

- `1 <= s.length <= 1000`
- `s` consists of English letters (lower-case and upper-case), `','` and `'.'`.
- `1 <= numRows <= 1000`