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

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

int main(){
    ios_base::sync_with_stdio(false);
    cin >> Tf >> Vf >> Hf >> Td >> Vd >> Hd;
    Td -= Tf;
    double tlees = sqrt(2*Hf);
    double tviz = (Td*Vd)/(Vd-Vf);
    if (tviz < 1e-9 || tlees < tviz + 1e-9) {//nem eri el vizszintesen, leesik
        cout << fixed << setprecision(8) << 2*tlees*Vf/Vd + Td + Tf << endl;
        return 0;
    }
    //mostantol vizszintesen tviz utanbarmikor eleri
    double v0 = sqrt(6*Hd);
    double tfeler = v0 / 3;
    if (((tviz + 1e-9 > tfeler + Td) ? Hd : (v0*(tviz-Td)-1.5*(tviz-Td)*(tviz-Td))) >= Hf-tviz*tviz/2) {
        cout << fixed << setprecision(8) << 2*tviz*Vf/Vd + Td + Tf << endl;
        return 0;
    }
    //nem eri el tvizben

    double t = sqrt(2*(Hf-Hd)); //frizbi Hd magasan
    if (t > Td + tfeler - 1e-9) {//feler Hd magasra
        cout << fixed << setprecision(8) <<  t + t*Vf/Vd + Tf << endl;
        return 0;
    }
    //nem er fel Hd magasra => rogton ugrik,
    double b = (v0 - 3*Td)/2;
    double c = (3*Td*Td/2 - v0*Td - Hf)/2;
    t = (-b-sqrt(b*b-4*c))/2;
    cout << fixed << setprecision(8) << t + t*Vf/Vd + Tf << endl;

    return 0;
}