import java.util.*;
import java.io.*;

public class Main {
    public static void main(String[] args) throws Exception {

        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        String[] str = br.readLine().split(" ");
        int n = Integer.parseInt(str[0]);
        
        String[] as = br.readLine().split(" ");
        int[] aArr = new int[n];
        aArr[0] = Integer.parseInt(as[0]);
        long ans = 1;
        for(int i = 1 ; i < n ; i++){
            aArr[i] = Integer.parseInt(as[i]);
            int min = Math.min(aArr[i-1] , aArr[i]);
            ans *= min;
            ans %= 998244353;
        }
        
        System.out.println(ans);
        
    }

}