Mod = 987654321 N=int(input()) N //=2 D = [0,1,2] K = 1 for i in range(3,N+1): K *= D[i-1] K %= Mod A = 2*D[i-1] for j in range(1, i-1): A += (D[j]*D[i-j-1])%Mod D.append( A % Mod) print(D[N])