#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using namespace atcoder;
using ll=long long;
using ld=long double;
ld pie=3.141592653589793;
ll inf=14449999999999;
ll mod=998244353;
int main(){
    ll n,a,b;
    cin >> n >> a >> b;
    vector<ll>x(n+1,1);
    for (ll i = 1; i <=n; i++)
    {
        x[i]=x[i-1]*i;
        x[i]%=mod;
    }
    if (a==b)
    {
        ll ans=x[n];
        ans+=mod-x[n-1];
        ans%=mod;
        ans+=mod-x[n-1];
        ans%=mod;
        cout << ans << endl;
    }else{
        ll ans=x[n];
        ans+=mod-x[n-1];
        ans%=mod;
        ans+=mod-x[n-1];
        ans%=mod;
        ans+=x[n-2];
        ans%=mod;
        cout << ans << endl;
    }
}