#include <bits/stdc++.h>
#include <atcoder/modint>
#define rep(i,n) for(int i = 0;i<n;i++)
using namespace std;
using namespace atcoder;
using mint = modint998244353;
int main() {
    int n; cin >> n;
    vector<int>a(n);
    rep(i, n) cin >> a[i];
    mint ways = 1;
    rep(i,n-1) ways*=min(a[i], a[i+1]);
    cout << ways.val() << endl;
    return 0;
}