package main

import . "fmt"

func main() {
	var n int
	Scan(&n)
	a := make([]int, n)
	for i := range a {
		Scan(&a[i])
	}
	ans := 1
	for i := range a[1:] {
		ans = ans * min(a[i], a[i+1]) % 998244353
	}
	Println(ans)
}