Stone Game 7

The stone game is played by two people who take stones in alternating turns.

There are $N$ stones on the table. Sang-Keun and Chang-Young take turns, and on one turn a player takes exactly $4^x$ stones. Here $x$ is an integer with $x \ge 0$, so the possible counts are 1, 4, 16, 64, and so on. The player who has no legal way to take stones on their turn loses the game.

Both players play perfectly. Write a program that finds the winner. Sang-Keun starts the game.

The first line contains the number of stones $N$. ($1 \le N \le 1{,}000{,}000{,}000{,}000$)

Print SK if Sang-Keun wins the game, or CY if Chang-Young wins.