import sys

# sys.setrecursionlimit(200005)
# sys.set_int_max_str_digits(200005)
int1 = lambda x: int(x)-1
pDB = lambda *x: print(*x, end="\n", file=sys.stderr)
p2D = lambda x: print(*x, sep="\n", end="\n\n", file=sys.stderr)
def II(): return int(sys.stdin.readline())
def LI(): return list(map(int, sys.stdin.readline().split()))
def LLI(rows_number): return [LI() for _ in range(rows_number)]
def LI1(): return list(map(int1, sys.stdin.readline().split()))
def LLI1(rows_number): return [LI1() for _ in range(rows_number)]
def SI(): return sys.stdin.readline().rstrip()

dij = [(0, 1), (-1, 0), (0, -1), (1, 0)]
# dij = [(0, 1), (-1, 0), (0, -1), (1, 0), (1, 1), (1, -1), (-1, 1), (-1, -1)]
# inf = -1-(-1 << 31)
inf = -1-(-1 << 62)

# md = 10**9+7
md = 998244353

n = II()
aa = [-1 if c == "?" else int(c)%3 for c in SI()]

s = [1, 0, 0]
ans = 0
for a in aa:
    ns = [0, 0, 0]
    if a == -1:
        for i in range(3):
            for j in range(3):
                ns[(i+j)%3] += s[i]*(3+(j == 0))%md
    else:
        for i in range(3):
            ns[(i+a)%3] += s[i]%md
    s = ns
    ans+=s[0]
    ans%=md
    s[0]+=1
print(ans)