#include #define REP(i, n) for(int i = 0; (i) < (n); (i)++) #define INF 5000000000000000 using namespace std; struct Edge{ int to; long weight; Edge(int t, long w) : to(t), weight(w) {} }; long modpow(long a, long n, long mod) { long res = 1; while (n > 0) { if (n & 1) res = res * a % mod; a = a * a % mod; n >>= 1; } return res; } // a^{-1} mod を計算する long modinv(long a, long mod) { return modpow(a, mod - 2, mod); } struct compare1 { bool operator()(const pair& value, const long& key) { return (value.first < key); } bool operator()(const long& key, const pair& value) { return (key < value.first); } }; struct RMQ { vector a; int inf = 2000000000; // 2*10^9 int n = 1; RMQ(int n_ = 1){ init(n_); } void init(int n_ = 1){ while(n < n_) n *= 2; a.resize(2*n-1); REP(i, 2*n-1) a[i] = inf; } //k番目の値(0-indexed)をbに変更 void update(int k, int b){ k += n-1; a[k] = b; while(k > 0){ k = (k-1)/2; a[k] = min(a[2*k+1], a[2*k+2]); } } //[a,b)の最小値を返す際に呼ぶ関数 int query_first(int c, int b){ return query(c, b, 0, 0, n); } //k : 節点番号, l, rはその接点が[l, r)に対応することを示す int query(int c, int b, int k, int l, int r){ if(r <= c || b <= l) return inf; if(c <= l && r <= b) return a[k]; else{ int vl = query(c, b, k*2+1, l, (l+r)/2); int vr = query(c, b, k*2+2, (l+r)/2, r); return min(vl, vr); } } }; struct UnionFind { vector par; vector rank; UnionFind(int n = 1){ init(n); } void init(int n = 1){ par.resize(n); rank.resize(n); REP(i, n) par[i] = i, rank[i] = 0; } int root(int x){ if(par[x] == x) return x; else return par[x] = root(par[x]); } bool issame(int x, int y){ return root(x) == root(y); } bool merge(int x, int y){ x = root(x); y = root(y); if(x == y) return false; if(rank[x] < rank[y]) swap(x, y); if(rank[x] == rank[y]) rank[x]++; par[y] = x; return true; } }; template struct weightedUnionFind{ vector par; vector rank; vector diff_weight; weightedUnionFind(int n = 1, Abel SUM_UNITY = 0){ init(n, SUM_UNITY); } void init(int n = 1, Abel SUM_UNITY = 0){ par.resize(n); rank.resize(n); diff_weight.resize(n); REP(i, n) par[i] = i, rank[i] = 0, diff_weight[i] = SUM_UNITY; } int root(int x){ if(par[x] == x) return x; else{ int r = root(par[x]); diff_weight[x] += diff_weight[par[x]]; return par[x] = r; } } Abel weight(int x){ root(x); return diff_weight[x]; } bool issame(int x, int y){ return root(x) == root(y); } bool merge(int x, int y, Abel w){ w += weight(x); w -= weight(y); x = root(x); y = root(y); if(x == y) return false; if(rank[x] < rank[y]) swap(x, y), w = -w; if(rank[x] == rank[y]) rank[x]++; par[y] = x; diff_weight[y] = w; return true; } Abel diff(int x, int y){ return weight(y) - weight(x); } }; using Graph = vector>; using P = pair; /* void dijkstra(int s, int V, Graph &G, long* d){ priority_queue, greater

> pque; fill(d, d + V, INF); d[s] = 0; pque.push(P(0, s)); while(!pque.empty()){ P p = pque.top(); pque.pop(); int now = p.second; if(d[now] < p.first) continue; REP(i, G[now].size()){ Edge e = G[now][i]; if(d[e.to] > d[now] + e.weight){ d[e.to] = d[now] + e.weight; pque.push(P(d[e.to], e.to)); } } } } */ int GCD(int a, int b){ if(b == 0) return a; if(a < b) return GCD(b, a); else return GCD(b, a%b); } struct BIT{ vector dat; int n = 1; BIT(int nn = 1){ init(nn); } void init(int nn = 1){ while(n < nn) n *= 2; dat.resize(n+1); REP(i, n+1) dat[i] = 0l; } //1-indexed!!!! void add(int i, long x){ while(i <= n){ dat[i] += x; i += (i&(-i)); } } //1-indexed!!!!! long get_sum(int i){ long ans = 0l; while(i > 0){ ans += dat[i]; i -= (i & (-i)); } return ans; } }; int main() { int P, Q; cin >> P >> Q; double p, q; p = (double)P; q = (double)Q; double x = 1.0; double y = p; double eps = p - 1.0; int kaisuu = 0; while(eps > 1.0e-8 && kaisuu < 10000000){ kaisuu++; x = sqrt(y); y = p + q * x * log2(x); eps = y - x * x; //cout << eps << endl; } if(x - 1.0 < 1.0e-5) x = 1.0; cout << fixed; cout << setprecision(8) << x << endl; return 0; }