#include <bits/stdc++.h>

using namespace std;

#define INF 100000000
#define YJ 1145141919
#define INF_INT_MAX 2147483647
#define INF_LL 9223372036854775
#define INF_LL_MAX 9223372036854775807
#define EPS 1e-10
#define MOD 1000000007
#define MOD9 998244353
#define Pi acos(-1)
#define LL long long
#define ULL unsigned long long
#define LD long double

#define int long long

using II = pair<int, int>;

int gcd(int a, int b) { return b != 0 ? gcd(b, a % b) : a; }
int lcm(int a, int b) { return a * b / gcd(a, b); }
int extgcd(int a, int b, int &x, int &y) { int g = a; x = 1; y = 0; if (b != 0) g = extgcd(b, a % b, y, x), y -= (a / b) * x; return g; }

#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define REP(i,n) FOR(i,0,n)
#define ALL(a)  begin((a)), end((a))
#define RALL(a) (a).rbegin(), (a).rend()
#define PB push_back
#define MP make_pair
#define SZ(a) int((a).size())

const int MAX_N = 200005;

int N;
int P[MAX_N];

int memo[MAX_N];
int myPow(int k) {
    if (k <= 1) {
        return 1;
    }
    if (memo[k] != -1) {
        return memo[k];
    }
    memo[k] = k * myPow(k-1);
    memo[k] %= MOD9;
    return memo[k];
}

int I[MAX_N];

signed main() {
    memset(memo, -1, sizeof(memo));
    // cerr << (myPow(12) * 110) % MOD9 << endl;
    // exit(0);
    cin >> N;
    REP(n, N) {
        cin >> P[n];
    }

    REP(n, N) {
        I[P[n]] = n;
    }

    int ans = 1;
    int l = I[0], r = I[0];
    int dd = 0;
    FOR(k,1,N+1) {
        int next_l = min(l, I[k]);
        int next_r = max(r, I[k]);
        int diff = abs(l - next_l) + abs(r - next_r);
        if (1 <= diff) {
            dd += diff-1;
        }
        
        if (l < I[k] && I[k] < r) {
            ans *= dd;
            ans %= MOD9;
            dd--;
        }
        r = next_r; l = next_l;
    }

    ans *= myPow(dd);
    ans %= MOD9;


    cout << ans << endl;

    return 0;
}