#include <bits/stdc++.h>

#define FOR(n, a, b) for(int n = (a); n < (b); ++n)
#define ALL(x) x.begin(), x.end()
#define pb push_back
#define st first
#define nd second

using namespace std;

typedef long long ll;
typedef pair<int, int> pint;
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef vector<pint> vii;

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(0);

    cout.precision(20);

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

    double Twyskoku = sqrt(2.0/3.0*Hd);     // czas wyskoku psa do Hd
    double Vwyskoku = 3 * Twyskoku;         // pred pocz psa do gory

    double Tcalk = sqrt(2 * Hf);            // calk czas spadania frysbie
    double TfHd = sqrt(2 * (Hf - Hd));      // czas spadania frysbie do Hd

    if (Vf >= Vd)                           // pies nigdy nie dogoni
    {
        double sf = Tcalk * Vf;             // gdzie doleci frysbie
        double T = sf / Vd;
        cout << (2 * T + Td) << "\n";
        return 0;
    }

    double sff = Vf * (Td - Tf);            // przewaga frysbie
    double Tdogonienia = sff / (Vd - Vf);   // cazs dogonienia

    double HfTd = Hf - 1 / 2.0 * (Td - Tf)*(Td - Tf); // wysokosc frysbie w Td

    if (Tdogonienia >= Tcalk)
    {
        double sf = Tcalk * Vf;             // gdzie doleci frysbie
        double T = sf / Vd;
        cout << (2 * T + Td) << "\n";
        return 0;
    }

    if (TfHd <= Twyskoku)
    {
        double Vspad = Td - Tf;

        double delta = (Vspad + Vwyskoku)*(Vspad + Vwyskoku) - 4*HfTd;
        double T = ( (Vspad + Vwyskoku) + sqrt(delta) ) / 2.0;
        double Tz= max(T, Tdogonienia);
        double s = Vf*(Tz);
        double Tp = s / Vd;
        cout << (Tz + Tp + Td) << "\n";
        return 0;
    }

    double T = max(Tdogonienia, TfHd);
    double s= Vf*(T + Td - Tf);
    double Tp = s / Vd;
    cout <<  (Tz + Tp + Td) << "\n";


    return 0;
}