#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using namespace atcoder;
using mint = modint998244353;
using ll = long long;
#define all(x) x.begin(), x.end()
#define rep(i, n) for (int i = 0; i < n; i++)

const int MAX = 520000;
const int MOD = 998244353;

long long fac[MAX], finv[MAX], inv[MAX];

void COMinit() {
    fac[0] = fac[1] = 1;
    finv[0] = finv[1] = 1;
    inv[1] = 1;
    for (int i = 2; i < MAX; i++){
        fac[i] = fac[i - 1] * i % MOD;
        inv[i] = MOD - inv[MOD%i] * (MOD / i) % MOD;
        finv[i] = finv[i - 1] * inv[i] % MOD;
    }
}

long long COM(int n, int k){
    if (n < k) return 0;
    if (n < 0 || k < 0) return 0;
    return fac[n] * (finv[k] * finv[n - k] % MOD) % MOD;
}
ll homop(int n, int k){
    if (n == k && k == 0) return 1;
    return COM(n + k - 1, k);
}
int main(void)
{
    COMinit();
    int n, b, w;
    cin >> n >> b >> w;
    int y = n - b - w;
    int z = n - b;
    mint ans = 0;
    rep(one, b + 2){
        if((y - one) % 2 == 0){
            int two = (y - one) / 2;
            int zero = b + 1 - one - two;
            int summ = z - one - 2 * two;
            mint pat = COM(b - 1, two) * COM(zero + one, zero);
            ans += pat * homop(two, summ);
        }
        y++;
        if((y - one) % 2 == 0){
            int two = (y - one) / 2;
            int zero = b + 1 - one - two;
            int summ = z - one - 2 * two;
            two--;
            mint pat = COM(b - 1, two) * COM(zero + one, zero);
            ans += 2 * pat * homop(two + 1, summ);
        }
        y++;
        if((y - one) % 2 == 0){
            int two = (y - one) / 2;
            int zero = b + 1 - one - two;
            int summ = z - one - 2 * two;
            two-=2;
            mint pat = COM(b - 1, two) * COM(zero + one, zero);
            ans += pat * homop(two + 2, summ);
        }
        y -= 2;

    }
    cout << ans.val() << endl;
    return 0;

}