/* -*- coding: utf-8 -*-
 *
 * 1709.cc:  No.1709 Indistinguishable by MEX - yukicoder
 */

#include<cstdio>
 
using namespace std;

/* constant */

const int MAX_N = 200000;
const int MOD = 998244353;

/* typedef */

typedef long long ll;

/* global variables */

int as[MAX_N];

/* subroutines */

/* main */

int main() {
  int n;
  scanf("%d", &n);

  for (int i = 0; i < n; i++) {
    int pi;
    scanf("%d", &pi);
    as[pi] = i;
  }
  //for (int i = 0; i < n; i++) printf("%d ", as[i]); putchar('\n');

  int x = 1, l = as[0], r = as[0], k = 0;
  //printf("0: [%d,%d] k=%d\n", l, r, k);

  for (int i = 1; i < n; i++) {
    int ai = as[i];
    if (ai < l) {
      k += l - ai - 1;
      l = ai;
    }
    else if (r < ai) {
      k += ai - r - 1;
      r = ai;
    }
    else {
      x = (ll)x * k % MOD;
      k--;
    }
    //printf("%d: [%d,%d] k=%d\n", i, l, r, k);
  }

  printf("%d\n", x);
  return 0;
}