Rearrange a string by writing its characters in a zigzag pattern across a given number of rows, then read row by row.
Given a string and a number of rows, write the characters in a zigzag pattern across the rows by moving downward and then diagonally upward repeatedly. After placing all characters, read the pattern row by row to form the final converted string.
Your task is to return that converted string.
This is a string arrangement problem where the main challenge is tracking which row each character belongs to as the zigzag repeats.
Input Format
- A string
s - An integer
numRows
Output Format
- Return the zigzag-converted string produced by reading the rows from top to bottom.
Constraints
1 <= s.length1 <= numRows- Characters are processed in order from left to right.
- If
numRows == 1ornumRows >= s.length, the result is the original string.
Example 1
Input
s = "PAYPALISHIRING", numRows = 3
Output
"PAHNAPLSIIGYIR"
Explanation
The characters are arranged in 3 rows in a zigzag shape, then concatenated row by row.
Example 2
Input
s = "PAYPALISHIRING", numRows = 4
Output
"PINALSIGYAHRPI"
Explanation
With 4 rows, the zigzag pattern changes, but the output is still formed by reading each row from top to bottom.
Show 1 more example
Example 3
Input
s = "A", numRows = 1
Output
"A"
Explanation
With only one row, the zigzag does not change the string.
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