#include #include #include #include #include #include #include #include #include #include #include #include #define vll vector #define vvvl vector #define vvl vector> #define VV(a, b, c, d) vector>(a, vector(b, c)) #define VVV(a, b, c, d) vector(a, vvl(b, vll (c, d))); #define re(c, b) for(ll c=0;c> p >> q; ld l = 1, r = 100000000000000; re(t, 200){ ld mid = (l+r)/2; ld x = mid * mid; ld y = p + q * mid * (log(mid)/log(2)) + 1e-8; //std::cout << mid << " " << x << " " << y << '\n'; if(x>y) r = mid; else l = mid; } //std::cout << fixed << setprecision(20) << log(4)/log(2) << '\n'; std::cout << fixed << setprecision(20) << l << '\n'; }