#include <bits/stdc++.h>
using namespace std;
using ll = long long;
#define rep(i,n) for (int i=0;i<(int)(n);i++)
const int MOD = 998244353;

int main(){
  ll n,a,b;
  cin>>n>>a>>b;
  ll nn=1;
  for(int i=1;i<=n-2;i++){
    nn*=i;
    nn%=MOD;
  }
  cout<<nn*((n-1)*(n-2)+(a!=b))%MOD<<endl;
}