#include #include using namespace std; using namespace atcoder; typedef long long ll; typedef long double ld; #define REP(i, n) for (int i = 0; i < (n); ++i) #define REPR(i, n) for (int i = n - 1; i >= 0; --i) #define FOR(i, m, n) for (int i = m; i < n; ++i) #define FORR(i, m, n) for (int i = m; i >= n; --i) #define ALL(v) (v).begin(),(v).end() #define ALLR(v) (v).rbegin(),(v).rend() #define fi first #define se second #define PB push_back #define EB emplace_back template using PQ = priority_queue; template using QP = priority_queue,greater>; templatevoid debug(const T &v,ll h,ll w){for(ll i=0;ivoid debug(const T &v,ll n){for(ll i=0;ivoid debug(const vector&v){debug(v,v.size());} templatevoid debug(const vector>&v){for(auto &vv:v)debug(vv,vv.size());} templatevoid debug(stack st){while(!st.empty()){cerr<void debug(queue st){while(!st.empty()){cerr<void debug(deque st){while(!st.empty()){cerr<void debug(PQ st){while(!st.empty()){cerr<void debug(QP st){while(!st.empty()){cerr<void debug(const set&v){for(auto z:v)cerr<void debug(const multiset&v){for(auto z:v)cerr<void debug(const array &a){for(auto z:a)cerr<void debug(const map&v){for(auto z:v)cerr<<"["<void foo(Head&& head, Tail&&... tail){cerr << head << " ";foo(move(tail)...);} templatebool chmax(T &a, const T &b) { if (abool chmin(T &a, const T &b) { if (b> a >> b >> c >> d; c=-c; cout << fixed << setprecision(10) << b-a*(d-b)/(c-a) << endl; }