MOD = 998244353

N = int(input())
P = list(map(int, input().split()))
pos = [-1] * N
for i in range(N):
    pos[P[i]] = i

l, r = pos[0], pos[0]

ans = 1

for i in range(1, N):
    if l < pos[i] < r:
        ans *= (r - l + 1 - i)
        ans %= MOD
    else:
        l = min(l, pos[i])
        r = max(r, pos[i])

print(ans)