A到K是流行的2048游戏类型中的游戏，带有字母表字母。
A to K is a game in the popular 2048 game genre using letters of the alphabet instead of numbers.
Swipe the board to move all tiles into the indicated direction.
When identical letters meet, they merge into the next letter of the alphabet.
Turn A's into B's, B's into C's and so on, and see if you can reach the game winning K tile.