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

int main() {
    cin.tie(0)->sync_with_stdio(0);

    int N, A, B;
    cin >> N >> A >> B;

    mint ans = 1;
    for (ll i = 1; i <= N; ++i) ans *= i;

    mint diff = 1;
    for (ll i = 1; i <= N - 2; ++i) diff *= i;
    ans += diff;
    if (A == B) ans -= diff;

    diff = 1;
    for (ll i = 1; i < N; ++i) diff *= i;
    ans -= 2 * diff;

    cout << ans.val() << "\n";

    return 0;
}