def solve_gu(n, b, w):
    ans = 0
    for bit in range(2 ** n):
        a = [0] * n
        cnt = 0
        for i in range(n):
            if 1 & (bit >> i):
                a[i] = 1
                cnt += 1
        if cnt != b:
            continue
        r = 0
        cnt = 0
        bef = -1
        for i in range(n):
            if a[i] == 0:
                cnt += 1
            else:
                if bef == -1:
                    r += max(cnt - 1, 0)
                else:
                    r += max(cnt - 2, 0)
                cnt = 0
                bef = i
        r += max(cnt - 1, 0)
        if r == w:
            ans += 1
    return ans

class Combinatorics():
    def __init__(self, mod, maxi = 4 * 10 ** 5):
        self.mod = mod
        self.maxi = maxi
        self.facs = [1, 1]
        self.factinvs = [1, 1]
        self.invs = [0, 1]
        for i in range(2, self.maxi + 1):
            self.facs.append((self.facs[-1] * i) % self.mod)
            self.invs.append((-self.invs[self.mod % i] * (self.mod // i)) % self.mod)
            self.factinvs.append((self.factinvs[-1] * self.invs[-1]) % self.mod)
            
    def choose(self, n, k) -> int:
        if k < 0 or k > n: return 0
        if k == 0 or k == n: return 1
        k = min(k, n - k)
        return (((self.facs[n] * self.factinvs[k]) % self.mod) * self.factinvs[n-k]) % self.mod
    
    def perm(self, n, k) -> int:
        return (self.choose(n, k) * self.facs[k]) % self.mod

    def homop(self, n, k) -> int:
        if n == k == 0:
            return 1
        return self.choose(n + k - 1, k)

    def factorial(self, n):
        return self.facs[n]


def solve(n, b, w):
    mod = 998244353
    y = n - b - w
    z = n - b
    C = Combinatorics(mod)
    ans = 0
    for one in range(0, b + 2):
        #X1 <= 1, XB <= 1 のとき、白駒は余計に置けない
        if (y - one) % 2 == 0:
            two = (y - one) // 2
            zero = b + 1 - one - two
            summ = z - one - 2 * two
            pat = C.choose(b - 1, two) * C.choose(zero + one, zero)
            pat %= mod
            ans += pat * C.homop(two, summ)
            ans %= mod
        #X1 >= 2, XB <= 1の場合、白駒は余計に1個置けるので、y -= 1
        y += 1
        if (y - one) % 2 == 0:
            two = (y - one) // 2
            zero = b + 1 - one - two
            summ = z - one - 2 * two
            two -= 1
            pat = C.choose(b - 1, two) * C.choose(zero + one, zero)
            pat %= mod
            ans += 2 * pat * C.homop(two + 1, summ) #対称性より、2倍する
            ans %= mod
        #X1 >= 2, XB >= 2の場合、もう1つ置ける
        y += 1
        if (y - one) % 2 == 0:
            two = (y - one) // 2
            zero = b + 1 - one - two
            summ = z - one - 2 * two
            two -= 2
            pat = C.choose(b - 1, two) * C.choose(zero + one, zero)
            pat %= mod
            ans += pat * C.homop(two + 2, summ) #対称性より、2倍する
            ans %= mod
        y -= 2
    return ans 

n, b, w = map(int,input().split())
#print(solve_gu(n, b, w))

print(solve(n, b, w))