#include <bits/stdc++.h>
#include <atcoder/modint>
using namespace std;
using ll = long long;
#define rep(i,n) for (int i=0;i<(int)(n);i++)
using mint = atcoder::modint998244353;

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