import sys,random,bisect
from collections import deque,defaultdict
from heapq import heapify,heappop,heappush
from itertools import permutations
from math import gcd,log

from math import sqrt, ceil
from bisect import bisect_left, bisect_right
from typing import Iterable


input = lambda :sys.stdin.readline().rstrip()
mi = lambda :map(int,input().split())
li = lambda :list(mi())

mod = 998244353

N = int(input())
A = li()

res = 1
for i in range(N-1):
    res *= min(A[i],A[i+1])
    res %= mod
print(res)