#include <iostream>
#include <vector>
#include <string>
#include <algorithm>
#include <cmath>
#include <stdio.h>
#define ll long long
#define ull unsigned long long

using namespace std;

int main()
{
    int tf, vf, hf, td, vd, hd;
    cin >> tf >> vf >> hf >> td >> vd >> hd;
    double gf = 1.0, gd = 3.0;

    double T1 = sqrt(2.0 * (double)(hf-hd) / gf);
    double T2 = (double)(vd * (tf - td)) / (double)(vf -vd);
    double T3 = sqrt(2.0 * hf / gf);

    double T = 0.0;
    if (T3 <= T2) {
        T = td + 2.0 * T3 * (double)vf / (double)vd;
    } else if (T2 >= T1) {
        T = (double)tf + T2 + T2 * (double)vf / (double)vd;
    } else {
        T = (double)tf + T1 + T1 * (double)vf / (double)vd;
    }

    //cout << T << endl;
    printf("%.6lf\n", T);

    return 0;
}