n = int(input())

s = input()
mod = 998244353
def solve(s, l, r):
    sn = s[l:r + 1]
    q = 0
    summ = 0
    for i in range(len(sn)):
        if sn[i] == '?':
            q += 1
        else:
            summ += int(sn[i])
    if summ % 3 == 0:
        ret = (pow(10, q, mod) - 1) * pow(3, mod - 2, mod) + 1
        ret %= mod
    else:
        ret = (pow(10, q, mod) - 1) * pow(3, mod - 2, mod)
        ret %= mod
    return ret

ans = 0
for l in range(0, n):
    for r in range(l, n):
        ans += solve(s, l, r)
        ans %= mod
print(ans)