#include <stdio.h>
#include <bits/stdc++.h>
#include <atcoder/all>
using namespace atcoder;
using mint = modint998244353;
using namespace std;
#define rep(i,n) for (int i = 0; i < (n); ++i)
#define Inf32 1000000001
#define Inf64 1000000000000000001



int main(){
	
	int n;
	cin>>n;
	vector<int> a(n);
	rep(i,n)cin>>a[i];
	mint ans = 1;
	rep(i,n-1){
		ans *= min(a[i],a[i+1]);
	}
	cout<<ans.val()<<endl;
	
	return 0;
}