#include #include using namespace std; using namespace atcoder; typedef int64_t lint; #define rep(i, n) for(int i=0; i; using vvi = vector>; template inline void vin(vector& v) { rep(i, v.size()) cin >> v.at(i); } template inline bool chmax(T& a, T b) { if (a < b) { a = b; return 1; } return 0; } template inline bool chmin(T& a, T b) { if (a > b) { a = b; return 1; } return 0; } template inline void drop(T x) { cout << x << endl; exit(0); } template void vout(vector v) { rep(i, v.size()) { cout << v.at(i) << ' '; } cout << endl; } constexpr lint LINF = LLONG_MAX/2; int main() { lint N, A, B; cin >> N >> A >> B; lint a=0, b=0, c=LINF, x=LINF, y, z; a = A*(N-1)*(-1) - B*(N%2); b = A*(N-1) - B*N; if (N >= 4) { if (N%2 == 1) c = A*(N-3)*(-1) + A*2 - B*(N%2+2); if (N%2 == 0) c = A*(N-2)*(-1) + A - B*(N%2+2); x = A*(N-3) - A*2 - B*(N-2); } std::cout << min(min(a, b), min(c, x)) << '\n'; }