use proconio::input;

fn main() {
    input! {
        n:usize,
        p:[usize;n],
    }
    const MOD: usize = 998244353;

    let mut ids = vec![0; n];
    for i in 0..n {
        ids[p[i]] = i;
    }

    let mut l = ids[0];
    let mut r = ids[0];
    let mut ans = 1;
    for i in 1..n {
        if l <= ids[i] && ids[i] <= r {
            ans *= r - l + 1 - i;
            ans %= MOD;
        } else {
            l = l.min(ids[i]);
            r = r.max(ids[i]);
        }
    }

    println!("{}", ans);
}