import sys
from itertools import islice, tee


def solve(in_):
    N = int(next(in_))
    A = tuple(map(int, next(in_).split()))
    MOD = 998244353

    ans = 1
    it0, it1 = tee(A)
    it = zip(it0, islice(it1, 1, None))
    for a, b in it:
        ans = (ans * min(a, b)) % MOD

    return ans


def main():
    answer = solve(sys.stdin)
    print(answer)


if __name__ == '__main__':
    main()