#include <bits/stdc++.h>

const int N = 1e7 + 5;
const int mod = 998244353;
int fra[N], inv[N];
int n, a, b, ans;

template <class T>
inline T Min(T x, T y) {return x < y ? x : y;}

inline void add(int &x, int y)
{
	x += y;
	x >= mod ? x -= mod : 0;
}

inline void dec(int &x, int y)
{
	x -= y;
	x < 0 ? x += mod : 0;
}

inline void add_prod(int &x, int u, int v)
{
	x = (1ll * u * v + x) % mod;
}

inline int quick_pow(int x, int k)
{
	int res = 1;
	while (k)
	{
		if (k & 1)
			res = 1ll * res * x % mod;
		x = 1ll * x * x % mod;
		k >>= 1;
	}
	return res;
}

inline int C(int n, int m)
{
	if (n < m)
		return 0;
	return 1ll * fra[n] * inv[n - m] % mod * inv[m] % mod;
}

inline int ask(int k)
{
	int res = C(k + b - 1, b - 1);
	dec(res, C(k + b - 1, k - 1));
	return res;
}

int main()
{
	scanf("%d%d%d", &n, &a, &b);
	if (a == 0 && b == 0)
		return puts("1"), 0;
	fra[0] = 1;
	for (int i = 1; i <= n; ++i)
		fra[i] = 1ll * fra[i - 1] * i % mod;
	inv[n] = quick_pow(fra[n], mod - 2);
	for (int i = n; i >= 1; --i)
		inv[i - 1] = 1ll * inv[i] * i % mod;

	for (int k = 0, km = Min(n - b, Min(a, b - 1)); k <= km; ++k)
	{
		int tmp = k ? ask(k) : 1;
		if (k == a)
		{
			int x = n - b - k, 
				y = a - k + 1;
			if (x >= 0)
				add_prod(ans, tmp, C(x + y - 1, y - 1));
		}
		else
		{
			int x = n - b - k - 1,
				y = a - k + 1;
			if (x >= 0)
				add_prod(ans, tmp, C(x + y - 1, y - 1));
		}
	}
	printf("%d\n", ans);
	return 0;
}