#include <stdio.h>

const int Mod = 998244353;

int main()
{
	int i, N, P[200001], P_inv[200001];
	scanf("%d", &N);
	for (i = 0; i < N; i++) scanf("%d", &(P[i]));
	for (i = 0; i < N; i++) P_inv[P[i]] = i;
	
	int k, l, r;
	long long fact[200001], ans = 1;
	for (i = 1, fact[0] = 1; i <= N; i++) fact[i] = fact[i-1] * i % Mod;
	l = P_inv[0];
	r = l;
	for (i = 1; i < N; i++) {
		k = P_inv[i];
		if (l <= k && k <= r) ans = ans * (r - l + 1 - i) % Mod;
		else if (k < l) l = k;
		else r = k;
	}
	printf("%lld\n", ans);
	fflush(stdout);
	return 0;
}