#include <bits/stdc++.h>
using namespace std;
#define int long long

int c, v, n;

signed main()
{
	cin >> n >> c >> v;
	int res = 1e18;
	for (int i = 1, t = 2; i <= 40; i ++ , t *= 2)
		res = min(res, ((n - t) / (t / 2) + bool((n - t) % (t / 2))) * v + (c + v) * i);
	cout << res;
	return 0;
}