MOD = 998244353
N = int(input())
P = list(map(int, input().split()))
if N == 1:
    print(1)
    exit()
PRev = [-1] * N
for i in range(N): PRev[P[i]] = i
L, R = PRev[0], PRev[1]
if L > R: L, R = R, L
Ans = 1
for i in range(2, N):
    Pos = PRev[i]
    if L <= Pos and Pos <= R:
        Ans *= R - L - i + 1
        Ans %= MOD
    elif Pos < L: L = Pos
    else: R = Pos
print(Ans)