MOD = 998244353

def main():
    import sys
    input = sys.stdin.read().split()
    N = int(input[0])
    B = int(input[1])
    W = int(input[2])
    
    if B + W > N:
        print(0)
        return
    
    R = N - W
    numerator = 3 * B - R
    if numerator < 0 or numerator % 2 != 0:
        print(0)
        return
    
    k = numerator // 2
    if k < 0 or k > B - 1:
        print(0)
        return
    
    m = B - k
    n = N - m - 1
    if n < 0 or m < 0 or m > n:
        print(0)
        return
    
    # Precompute fact and inv_fact up to max needed value
    max_n = max(n, B)
    fact = [1] * (max_n + 1)
    for i in range(1, max_n + 1):
        fact[i] = fact[i-1] * i % MOD
    inv_fact = [1] * (max_n + 1)
    inv_fact[max_n] = pow(fact[max_n], MOD-2, MOD)
    for i in range(max_n-1, -1, -1):
        inv_fact[i] = inv_fact[i+1] * (i+1) % MOD
    
    def comb(n, k):
        if n < 0 or k < 0 or k > n:
            return 0
        return fact[n] * inv_fact[k] % MOD * inv_fact[n - k] % MOD
    
    res = comb(n, m)
    print(res)

if __name__ == '__main__':
    main()