#include <algorithm>
#include <cassert>
#include <cstdio>
#include <cmath>
#include <deque>
#include <iostream>
#include <map>
#include <unordered_set>
#include <unordered_map>
#include <vector>
#include <set>

using namespace::std;




int main() {
  ios::sync_with_stdio(false);
  long long n, a, b, m = 998244353;
  cin >> n >> a >> b;
  vector<long long> f(n + 1);
  f[0] = 1;
  for (int i = 1; i <= n; ++i) f[i] = (f[i - 1] * i) % m;
  long long r = (f[n] + ((m - 2) * f[n - 1]) % m) % m;
  if (a != b) r = (r + f[n - 2]) % m;
  
  cout << r << endl;

  
  return 0;
}