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

class Main{       
    private static final long mod = 998244353;

    void solver(){      
        // 次に行くにはどちらかの最小の道のりしかない
        int n = in.ni();
        long [] A = in.LongArray(n);
        long ans = 1 ;
        for(int i = 0 ; i < n - 1 ; i ++ ) {
            long min = Math.min(A[i],A[i+1]);
            ans = ( ans * min ) % mod;
        }
        out.print(ans);
    }   

    public static void main(String[] args){
        out = new PrintWriter(System.out);
        in  = new In();
        new Main().solver();
        out.flush();
    }

    private static PrintWriter out ;
    private static In in ;
    
}

class Pair{
    int first;
    int second;
    Pair(int first,int second) {
        this.first = first;
        this.second = second;
    }
    int F(){
        return this.first;
    }
    int S(){
        return this.second;
    }

    //Comparator<Pair> CM = Comparator.comparing(Pair::F).thenComparing(Pair::S);

    //Comparator<Pair> CM = Comparator.comparing(Pair::S).thenComparing(Pair::F);

}

class In{
    private final InputStream in = System.in;
    private static Scanner sc = new Scanner(System.in);
    private final byte[] buffer = new byte[1024];
    private int ptr = 0;
    private int buflen = 0;
    private boolean hasNextByte() {
        if (ptr < buflen) {
            return true;
        }else{
            ptr = 0;
            try {
                buflen = in.read(buffer);
            } catch (IOException e) {
                e.printStackTrace();
            }
            if (buflen <= 0) {
                return false;
            }
        }
        return true;
    }
    private int readByte() { if (hasNextByte()) return buffer[ptr++]; else return -1;}
    private static boolean isPrintableChar(int c) { return 33 <= c && c <= 126;}
    public boolean hasNext() { while(hasNextByte() && !isPrintableChar(buffer[ptr])) ptr++; return hasNextByte();}
    String ns() {
        if (!hasNext()) throw new NoSuchElementException();
        StringBuilder sb = new StringBuilder();
        int b = readByte();
        while(isPrintableChar(b)) {
            sb.appendCodePoint(b);
            b = readByte();
        }
        return sb.toString();
    }
    long nl() {
        if (!hasNext()) throw new NoSuchElementException();
        long n = 0;
        boolean minus = false;
        int b = readByte();
        if (b == '-') {
            minus = true;
            b = readByte();
        }
        if (b < '0' || '9' < b) {
            throw new NumberFormatException();
        }
        while(true){
            if ('0' <= b && b <= '9') {
                n *= 10;
                n += b - '0';
            }else if(b == -1 || !isPrintableChar(b)){
                return minus ? -n : n;
            }else{
                throw new NumberFormatException();
            }
            b = readByte();
        }
    }
    int ni() {
        long nl = nl();
        if (nl < Integer.MIN_VALUE || nl > Integer.MAX_VALUE) throw new NumberFormatException();
        return (int) nl;
    }
    double nd() { 
        return Double.parseDouble(ns());
    }
    BigInteger bi() {
        return sc.nextBigInteger();
    }
    BigDecimal bd() {
        return sc.nextBigDecimal();
    }
    int [] IntArray(int n) {
        final int [] Array = new int [n];
        for(int i = 0 ; i < n ; i ++ ) {
            Array[i] = ni();
        }
        return Array;
    }
    int [][] IntArray(int n , int m) {
        final int [][] Array = new int [n][m];
        for(int i = 0 ; i < n ; i ++ ) {
            Array[i] = IntArray(m);
        }
        return Array;
    }   
    long [] LongArray(int n) {
        final long [] Array = new long [n];
        for(int i = 0 ; i < n ; i ++ ) {
            Array[i] = nl();
        }
        return Array;
    }
    long [][] LongArray(int n , int m) {
        final long [][] Array = new long [n][m];
        for(int i = 0 ; i < n ; i ++ ) {
            Array[i] = LongArray(m);
        }
        return Array;
    }
    String [] StringArray(int n) {
        final String [] Array = new String [n];
        for(int i = 0 ; i < n ; i ++ ) {
            Array[i] = ns();
        }
        return Array;
    }
    char [][] CharArray(int n , int m) {
        final char [][] Array = new char [n][m];
        for(int i = 0 ; i < n ; i ++ ) {
            Array[i] = ns().toCharArray();
        }
        return Array;
    }
}