Stone Game 5

Stone Game is a game for two players.

There are $N$ stones on a table. Sanggeun and Changyoung take turns, and on a turn a player can take 1 stone or 3 stones. Whoever takes the last stone wins.

Sanggeun goes first. Write a program that finds the winner when both players play perfectly.

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

Print SK on one line if Sanggeun wins, or CY if Changyoung wins.