#define _USE_MATH_DEFINES
#include <bits/stdc++.h>
using namespace std;
#define FOR(i,m,n) for(int i=(m);i<(n);++i)
#define REP(i,n) FOR(i,0,n)
#define ALL(v) (v).begin(),(v).end()
using ll = long long;
constexpr int INF = 0x3f3f3f3f;
constexpr long long LINF = 0x3f3f3f3f3f3f3f3fLL;
constexpr double EPS = 1e-8;
constexpr int MOD = 998244353;
// constexpr int MOD = 1000000007;
constexpr int DY4[]{1, 0, -1, 0}, DX4[]{0, -1, 0, 1};
constexpr int DY8[]{1, 1, 0, -1, -1, -1, 0, 1};
constexpr int DX8[]{0, -1, -1, -1, 0, 1, 1, 1};
template <typename T, typename U>
inline bool chmax(T& a, U b) { return a < b ? (a = b, true) : false; }
template <typename T, typename U>
inline bool chmin(T& a, U b) { return a > b ? (a = b, true) : false; }
struct IOSetup {
  IOSetup() {
    std::cin.tie(nullptr);
    std::ios_base::sync_with_stdio(false);
    std::cout << fixed << setprecision(20);
  }
} iosetup;

int main() {
  using Matrix = array<array<ll, 2>, 2>;
  ll n; int a, b; cin >> n >> a >> b;
  const auto mul = [&](const Matrix& m1, const Matrix& m2) -> Matrix {
    Matrix res{array<ll, 2>{LINF, LINF}, array<ll, 2>{LINF, LINF}};
    REP(i, 2) REP(j, 2) {
      if (m1[i][j] == LINF) continue;
      REP(k, 2) REP(l, 2) {
        if (m2[k][l] == LINF) continue;
        chmin(res[i][l], m1[i][j] + m2[k][l] + (j == k ? a : -a));
      }
    }
    return res;
  };
  Matrix dp{array<ll, 2>{b, LINF}, array<ll, 2>{LINF, -b}}, tmp = dp;
  for (--n; n > 0; n >>= 1) {
    if (n & 1) dp = mul(dp, tmp);
    tmp = mul(tmp, tmp);
  }
  ll ans = LINF;
  REP(i, 2) chmin(ans, *min_element(ALL(dp[i])));
  cout << ans << '\n';
  return 0;
}