/**
 *  - Meet Brahmbhatt
 *  - Hard work always pays off
**/
#include"bits/stdc++.h"
using namespace std;

#ifdef MeetBrahmbhatt
#include "debug.h"
#else
#define dbg(...) 72
#endif

#define endl "\n"
#define int long long

const long long INF = 4e18;
const int32_t M = 1e9 + 7;
const int32_t MM = 998244353;

void solve() {
    int n, a , b;
    cin >> n >> a >> b;
    vector<int> F(n + 1, 1);
    for (int i = 1; i <= n; i++) {
        F[i] = (F[i - 1] * i) % MM;
    }
    int ans = F[n] - F[n - 1] - F[n - 1];
    ans += MM;
    ans %= MM;
    if (a != b) {
        ans += F[n - 2];
        ans %= MM;
    }
    cout << ans;
}

signed main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout << fixed << setprecision(9);
    int tt = 1;
    // cin >> tt;
    while (tt--) solve();
    return 0;
}