#include <algorithm>
#include <cassert>
#include <cstdio>
#include <cmath>
#include <deque>
#include <iostream>
#include <map>
#include <unordered_set>
#include <unordered_map>
#include <vector>
#include <set>

using namespace::std;




int main() {
  ios::sync_with_stdio(false);
  const long long m = 998244353;
 
  long long n, a, b, r = 1;
  cin >> n >> b;
  for (int i = 1; i < n; ++i) {
    cin >> a;
    r *= min(b, a);
    r %= m;
    b = a;
  }
  cout << r << endl;
  
  return 0;
}