import fractions
from functools import lru_cache
N=int(input())
@lru_cache(maxsize=None)
def A(N):
    if N==0:
        return fractions.Fraction(1)
    if N==1:
        return fractions.Fraction(1)
    if N>0:
        return A(N-1)-10*A(N-2)
    else:
        return (A(N+1)-A(N+2))/10
ans=-A(N-2)
print(ans)