#include <iostream>
#include <iomanip>
#include <cmath>
using namespace std;

double Tf, Vf, Hf, Td, Vd, Hd;

constexpr double eps = 1e-9;

double solve(){
	const double landing_time = sqrt(2 * Hf);
	if(Vd <= Vf + eps) return Td + 2 * Vf * landing_time / Vd;
	const double catch_time = Td * Vd / (Vd - Vf);
	if(catch_time >= landing_time - eps) return Td + 2 * Vf * landing_time / Vd;
	double l = max(catch_time, sqrt(2 * (Hf - Hd)));
	double r = landing_time;
	for(int i=0;i<150;++i) {
		double m = (l+r)/2;
		double h = Hf - m*m/2;
		double jmpt = sqrt(2.0/3.0) * (sqrt(Hd) - sqrt(Hd - h));
		if(m - jmpt > Td) r = m;
		else l = m;
	}
	return l * (1.0 + Vf / Vd);
}

int main(){
	cin >> Tf >> Vf >> Hf >> Td >> Vd >> Hd;
	Td -= Tf;
	cout << fixed << setprecision(12) << Tf + solve() << '\n';
}