MOD = 998244353 N = int(input()) def dot(A, B): Ah, Bh, Bw = len(A), len(B), len(B[0]) C = [[0 for _ in range(Bw)] for _ in range(Ah)] for i in range(Ah): for j in range(Bw): for k in range(Bh): C[i][j] += A[i][k] * B[k][j] % MOD C[i][j] %= MOD return C # Mのk乗を効率的に計算する def powmat(M, k): k -= 1 Mc = M.copy() while k > 0: if k & 1 == 1: Mc = dot(Mc, M) M = dot(M, M) # Mの(2のi乗)の乗 を計算する k >>= 1 return Mc M = [[1, 1], [1, 0]] F = [[1], [0]] Mn = powmat(M, N) G = dot(Mn,F) print((G[0][0]-1)%MOD)