Conveyor Reverse K Block Segments

Items ride a conveyor as a single string of lowercase letters. A relabeling machine processes the string in blocks of 2k characters from left to right. Within each block it reverses the first k characters and leaves the next k characters as they are. For the final partial block, the standard rule applies:

• If fewer than k characters remain, reverse all of them.
• If between k and 2k characters remain, reverse the first k and leave the rest as they are.

Print the resulting string.

Input format

Line 1: an integer k. Line 2: a non-empty string of lowercase English letters.

Output format

A single line: the transformed string.

Constraints

• 1 <= k <= 100000
• 1 <= length of the string <= 100000
• The string consists only of lowercase English letters (a-z).