#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
typedef long double ld;
#define rep(i, a, n) for (int i = (a); i < (n); i++)
#define per(i, a, n) for (int i = (n) - 1; i >= (a); i--)
double Tf,Vf,Hf,Td,Vd,Hd;
double h(double s){
    return Hf-(s*s)/(2*Vf*Vf);
}
double f(double s){
    return Td+max(s/Vd, (sqrt(6*Hd)-sqrt(6*Hd-6*h(s)))/3);
}
double g(double s){
    return Tf+s/Vf;
}
int main(void)
{
	ios_base::sync_with_stdio(false);

	cin >> Tf >> Vf >> Hf >> Td >> Vd >> Hd;
    double konec=sqrt(2*Hf)*Vf;
    double start=sqrt(2*Hf-2*Hd)*Vf;
    while(konec-start>0.000000001){
        double middle=(start+konec)/2;
        if(f(middle)<g(middle)) konec=middle;
        else start=middle;
    }
    double ted=(start+konec)/2;
    cout << setprecision(9) << fixed;
    cout << max(f(ted),g(ted))+ted/Vd << endl;
}