#include <bits/stdc++.h>
using namespace std;
const int INF = 1e9;
using ll = long long;
using inv = vector<int>;
using stv = vector<string>;
using pint = pair<int,int>;
#define FOR(i,l,r) for(int i=(l); i<(r); i++)
#define rep(i,r) for(int i=0; i<(r); i++)
#define repl(i,r) for(long long i=0; i<(r); i++)
#define FORl(i,l,r) for(long long i=(l); i<(r); i++)
#define INFL ((1LL<<62)-(1LL<<31))
#define pb(x) push_back(x)
#define CIN(x) cin >> x

const ll MOD = 998244353LL;

int main(){
  int N; cin >> N;
  vector<ll> A(N);
  
  rep(i,N) cin >> A[i];
  
  ll ans = 1LL;
  
  for(int i=N-1; i>= 1; i--){
    ans = (ans*min(A[i],A[i-1]))%MOD;
  }
  
  
  
  cout << ans%MOD << endl;
  
  
}