#include #include #include #include #include #include #include #include #include #define rep(i, a, b) for (int i = int(a); i < int(b); i++) using namespace std; using ll = long long int; // NOLINT using P = pair; // clang-format off #ifdef _DEBUG_ #define dump(...) do{ cerr << __LINE__ << ":\t" << #__VA_ARGS__ << " = "; debug_print(__VA_ARGS__); } while(false) template void debug_print(const T &t, const Ts &...ts) { cerr << t; ((cerr << ", " << ts), ...); cerr << endl; } template struct IsVector : std::false_type {}; template struct IsVector> : std::true_type {}; template ostream &dump_v(const vector &vec, ostream &os = cerr, int indent = 0) { if constexpr (IsVector::value) { os << string(indent, ' ') << "[\n"; for (auto it = vec.begin(); it != vec.end(); ++it) dump_v(*it, os, indent + 2) << ",\n"; os << string(indent, ' ') << "]"; } else { os << string(indent, ' ') << "["; for (auto it = vec.begin(); it != vec.end(); ++it) os << (it == vec.begin() ? "" : ", ") << *it; os << "]"; } return indent == 0 ? os << endl : os; } #else #define dump(...) do{ } while(false) #define dump_v(...) do{ } while(false) #endif template vector make_v(size_t a, T b) { return vector(a, b); } template auto make_v(size_t a, Ts... ts) { return vector(a, make_v(ts...)); } template bool chmin(T &a, const T& b) { if (a > b) {a = b; return true; } return false; } template bool chmax(T &a, const T& b) { if (a < b) {a = b; return true; } return false; } template void print(const T& t, const Ts&... ts) { cout << t; ((cout << ' ' << ts), ...); cout << '\n'; } constexpr static struct PositiveInfinity { template constexpr operator T() const { return numeric_limits::max() / 2; } constexpr auto operator-() const; } inf; // NOLINT constexpr static struct NegativeInfinity { template constexpr operator T() const { return numeric_limits::lowest() / 2; } constexpr auto operator-() const; } NegativeInfinityVal; constexpr auto PositiveInfinity::operator-() const { return NegativeInfinityVal; } constexpr auto NegativeInfinity::operator-() const { return inf; } // clang-format on #include int main() { cin.tie(nullptr); ios::sync_with_stdio(false); double x, y; cin >> x >> y; x /= 100; y /= 100; double ans = x * y + (1 - x) * (1 - y); cout << fixed << setprecision(15) << x * y / ans * 100 << endl; return 0; }