713 B | 713 chars
import sys
from math import sqrt, pi, sin, factorial, ceil, floor
from datetime import datetime, timedelta
BLANK = " "
#inp = input
inp = lambda : sys.stdin.readline()[:-1].strip()
mii = lambda x = BLANK : [*map(int,inp().split(x))]
mfi = lambda x = BLANK : [*map(float,inp().split(x))]
ii = lambda : int(inp())
fi = lambda : float(inp())
p = print
def solve():
s = input()
i = 0
ans = ""
while i < len(s):
if i + 2 < len(s):
z = set(s[i:i+3])
if len(z) == 3:
ans += "C"
i += 3
continue
ans += {"R": "S", "B": "K", "L": "H"}[s[i]]
i += 1
p(ans)
if __name__ == "__main__":
tc = 1
for t in range(1, tc+1):
ret = solve()