use std::io::*; const MOD: usize = 998244353; fn main() { let mut s: String = String::new(); std::io::stdin().read_to_string(&mut s).ok(); let mut itr = s.trim().split_whitespace(); let n: usize = itr.next().unwrap().parse().unwrap(); let p: Vec<usize> = (0..n) .map(|_| itr.next().unwrap().parse().unwrap()) .collect(); let mut q = vec![0; n]; for i in 0..n { q[p[i]] = i; } let mut l = q[0]; let mut r = q[0]; let mut ans = 1; for i in 1..n { let nl = std::cmp::min(l, q[i]); let nr = std::cmp::max(r, q[i]); if nr == r && nl == l { ans = ans * (r - l + 1 - i) % MOD; } l = nl; r = nr; } println!("{}", ans); }