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# 0006. ZigZag Conversion

<https://leetcode.com/problems/zigzag-conversion>

## Description

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`

## ac

```java
```