Special Keyboard

Limits 1s, 512 MB

Herok, the fastest typist in the world, has a special keyboard. The keyboard only has nnn different keys each representing a different character. All the keys are on a single line. The first key at the leftmost position, the second one at the second from left position, and so on. As it’s a one-line keyboard, he can type with two fingers only, otherwise, it gets too complicated.

This is a companion discussion topic for the original entry at https://toph.co/p/special-keyboard