#include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include using namespace std; using i64 = int_fast64_t; using ui64 = uint_fast64_t; using db = long double; using pii = pair; using pli = pair; using pll = pair; using pdi = pair; template using vct = vector; template using heap = priority_queue; template using minheap = priority_queue, greater>; template constexpr T inf = numeric_limits::max() / 4 - 1; constexpr int dx[9] = {1, 0, -1, 0, 1, -1, -1, 1, 0}; constexpr int dy[9] = {0, 1, 0, -1, 1, 1, -1, -1, 0}; constexpr long double gold = 1.618033988; constexpr long double eps = 1e-15; #define stdout_precision 10 #define stderr_precision 2 #define itr(i,v) for(auto i = begin(v); i != end(v); ++i) #define ritr(i,v) for(auto i = rbegin(v); i != rend(v); ++i) #define rep(i,n) for(int i = 0; i < (n); ++i) #define all(v) begin(v), end(v) #define rall(v) rbegin(v), rend(v) #define fir first #define sec second #define fro front #define bac back #define u_map unordered_map #define u_set unordered_set #define l_bnd lower_bound #define u_bnd upper_bound #define rsz resize #define ers erase #define emp emplace #define emf emplace_front #define emb emplace_back #define pof pop_front #define pob pop_back #define mkp make_pair #define mkt make_tuple #define popcnt __builtin_popcount struct setupper { setupper() { ios::sync_with_stdio(false); std::cin.tie(nullptr); std::cout.tie(nullptr); std::cerr.tie(nullptr); std::cout << fixed << setprecision(stdout_precision); std::cerr << fixed << setprecision(stderr_precision); // #ifdef Local // std::cerr << "\n---stderr---\n"; // auto print_atexit = []() { // std::cerr << "Exec time : " << clock() / (double)CLOCKS_PER_SEC * 1000.0 << "ms\n"; // std::cerr << "------------\n"; // }; // atexit((void(*)())print_atexit); // #endif } } setupper_; namespace std { template void hash_combine(size_t &seed, T const &key) { seed ^= hash()(key) + 0x9e3779b9 + (seed << 6) + (seed >> 2); } template struct hash> { size_t operator()(pair const &pr) const { size_t seed = 0; hash_combine(seed,pr.first); hash_combine(seed,pr.second); return seed; } }; template ::value - 1> struct hashval_calc { static void apply(size_t& seed, Tup const& tup) { hashval_calc::apply(seed, tup); hash_combine(seed,get(tup)); } }; template struct hashval_calc { static void apply(size_t& seed, Tup const& tup) { hash_combine(seed,get<0>(tup)); } }; template struct hash> { size_t operator()(tuple const& tup) const { size_t seed = 0; hashval_calc>::apply(seed,tup); return seed; } }; } template istream &operator>> (istream &s, pair &p) { return s >> p.first >> p.second; } template ostream &operator<< (ostream &s, const pair p) { return s << p.first << " " << p.second; } template ostream &operator<< (ostream &s, const vector &v) { for(size_t i = 0; i < v.size(); ++i) s << (i ? " " : "") << v[i]; return s; } #define dump(...) cerr << " [ " << __LINE__ << " : " << __FUNCTION__ << " ] " << #__VA_ARGS__ << " : ";\ dump_func(__VA_ARGS__) template void dump_func(T x) { cerr << x << '\n'; } template void dump_func(T x, Rest ... rest) { cerr << x << ","; dump_func(rest...); } template T read() { T x; return cin >> x, x; } template void write(T x) { cout << x << '\n'; } template void write(T x, Rest ... rest) { cout << x << ' '; write(rest...); } void writeln() {} template void writeln(T x, Rest ... rest) { cout << x << '\n'; writeln(rest...); } #define esc(...) writeln(__VA_ARGS__), exit(0) namespace updater { template static void add(T &x, const T &y) { x += y; } template static void ext_add(T &x, const T &y, size_t w) { x += y * w; } template static void mul(T &x, const T &y) { x *= y; } template static void ext_mul(T &x, const T &y, size_t w) { x *= (T)pow(y,w); } template static bool chmax(T &x, const T &y) { return x < y ? x = y,true : false; } template static bool chmin(T &x, const T &y) { return x > y ? x = y,true : false; } }; using updater::chmax; using updater::chmin; template T minf(const T &x, const T &y) { return min(x,y); } template T mixf(const T &x, const T &y) { return max(x,y); } bool bit(i64 n, uint8_t e) { return (n >> e) & 1; } i64 mask(i64 n, uint8_t e) { return n & ((1 << e) - 1); } int ilog(uint64_t x, uint64_t b = 2) { return x ? 1 + ilog(x / b,b) : -1; } template i64 binry(i64 ok, i64 ng, const F &fn) { while (abs(ok - ng) > 1) { i64 mid = (ok + ng) / 2; (fn(mid) ? ok : ng) = mid; } return ok; } template void init(A (&array)[N], const T &val) { fill((T*)array,(T*)(array + N),val); } template void cmprs(A ary[], size_t n) { vector tmp(ary,ary + n); tmp.erase(unique(begin(tmp),end(tmp)), end(tmp)); for(A *i = ary; i != ary + n; ++i) *i = l_bnd(all(tmp),*i) - begin(tmp); } template void cmprs(vector &v) { vector tmp = v; sort(begin(tmp),end(tmp)); tmp.erase(unique(begin(tmp),end(tmp)), end(tmp)); for(auto i = begin(v); i != end(v); ++i) *i = l_bnd(all(tmp),*i) - begin(tmp); } template void for_subset(uint_fast64_t s, const F &fn) { uint_fast64_t tmp = s; do { fn(tmp); } while((--tmp &= s) != s); } double p,q; signed main() { cin>>p>>q; writeln(p*q/100/(p/100*q/100+(1-p/100)*(1-q/100))); }