This summer, ESCOM willl hold the XVIII Annual Drone Kaleidoscope (DK for short). During this event, a one-lane track is written as a string.

During the annual DK, several teams, one by one, perform a show as follows:

• Each team picks a different palindrome that actually appears somewhere on the track.
• Each team selects some subset of occurrences of their chosen palindrome, and places a drone in the leftmost character of the selected occurrences.
• To avoid radio noise within the team performance, that team's drone starting positions must be at least $$$k$$$ characters apart.
• Finally, the team flies their drones over the selected occurrences of the chosen palindrome.

A team's show value is $$$$$$ \text{(length of its palindrome)} \times \text{(number of drones it places)}. $$$$$$

For example, if we have $$$s=abaaba$$$ and $$$k=3$$$, a valid show configuration is to field $$$3$$$ teams as follows:

1. The first team chooses the palindrome $$$aba$$$ and launches $$$2$$$ drones with initial positions $$$\{1,4\}$$$. This team's show value is $$$3 \times 2=6$$$.
2. The second team chooses the palindrome $$$baab$$$ and launches $$$1$$$ drones with initial position $$$\{2\}$$$. This team's show value is $$$4 \times 1=4$$$.
3. The third team chooses the palindrome $$$a$$$ and launches $$$2$$$ drones with initial positions $$$\{1,6\}$$$. This team's show value is $$$1 \times 2=2$$$. Note that launching $$$3$$$ drones with initial positions $$$\{1,3,6\}$$$ is invalid, since starting positions should be at least $$$k=3$$$ characters apart.

The total show value in this example is $$$6+4+2=12$$$.

Your team is practicing to participate in this event. To practice flying a drone over a palindrome, your team needs to write a palindrome consisting only of lowercase letters. Given an integer $$$n$$$, print a palindrome of length $$$n$$$.

Recall that a palindrome is a string that reads the same backward as forward, for example, strings "z", "aba", "abccba" are palindromes, but strings "codeforces", "reality", "ab" are not.