import sys

# sys.setrecursionlimit(200005)
int1 = lambda x: int(x)-1
pDB = lambda *x: print(*x, end="\n", file=sys.stderr)
p2D = lambda x: print(*x, sep="\n", end="\n\n", file=sys.stderr)
def II(): return int(sys.stdin.readline())
def LI(): return list(map(int, sys.stdin.readline().split()))
def LLI(rows_number): return [LI() for _ in range(rows_number)]
def LI1(): return list(map(int1, sys.stdin.readline().split()))
def LLI1(rows_number): return [LI1() for _ in range(rows_number)]
def SI(): return sys.stdin.readline().rstrip()

# dij = [(0, 1), (-1, 0), (0, -1), (1, 0)]
dij = [(0, 1), (-1, 0), (0, -1), (1, 0), (1, 1), (1, -1), (-1, 1), (-1, -1)]
inf = (1 << 63)-1
# inf = (1 << 31)-1
# md = 10**9+7
# md = 998244353

md = 1000
n = II()
ans = -1+(n & 1)

# (a+r3b)(c+r3d)=(ac+3bd)+r3(ad+bc)
def merge(ab, cd):
    a, b = ab
    c, d = cd
    return [(a*c%md+3*b*d%md)%md, (a*d%md+b*c%md)%md]

base = [1, 1]
mat = [1, 0]
while n:
    if n & 1: mat = merge(mat, base)
    base = merge(base, base)
    n >>= 1

ans += mat[0]*2
print(ans%md)