#include <bits/stdc++.h>

using namespace std;
using ll = long long;
#define rep(i, s, t) for (ll i = s; i < (ll)(t); i++)
#define all(x) begin(x), end(x)
template <class T> bool chmin(T& x, T y) {
	return x > y ? (x = y, true) : false;
}
template <class T> bool chmax(T& x, T y) {
	return x < y ? (x = y, true) : false;
}

void solve() {
	ll n, a, b, c;
	cin >> n >> a >> b >> c;
	n *= 2;
	vector<ll> f(n);
	f[0] = 1;
	rep(i, 1, n) f[i] = f[i - 1] * i % n;
	vector<ll> cost(n, 1e18);
	priority_queue<pair<ll, int>, vector<pair<ll, int>>, greater<pair<ll, int>>> pq;
	cost[1] = 0;
	pq.push({0, 1});
	while(!pq.empty()) {
		auto [d, x] = pq.top();
		pq.pop();
		if(x == 0) break;
		if(cost[x] > d) continue;
		if(chmin(cost[(x + 1) % n], d + a)) pq.push({d + a, (x + 1) % n});
		{
			ll cx = x;
			for(ll cb = b; cb < n * a; cb *= b) {
				if(chmin(cost[cx], d + cb)) pq.push({d + cb, cx});
				cx = cx * x % n;
			}
		}
		if(chmin(cost[f[x]], d + c)) pq.push({d + c, f[x]});
	}
	cout << cost[0] << '\n';
}

int main() {
	ios::sync_with_stdio(false);
	cin.tie(nullptr);
	cout << fixed << setprecision(15);
	int t = 1;
	// cin >> t;
	while (t--) solve();
}