#include <cstdio>
#include <cstring>
#include <algorithm>
#include <cmath>
#include <iostream>
#include <string>
#include <set>
#include <map>
#include <vector>
#include <queue>
#define ll long long
#define db double
using namespace std;
const ll M = 998244353;
const ll N = 2e5 + 100;
ll n,a[N];
int main() {
	ll ans = 1;
	scanf("%lld",&n);
	for (ll i = 1;i <= n;i++) {
		scanf("%lld",&a[i]);
	}
	for (ll i = 1;i < n;i++) {
		ans *= min(a[i],a[i + 1]);
		ans %= M;
	}
	printf("%lld",ans);
	return 0;
}