#include <iostream>
#include <vector>
#include <cmath>
using namespace std;
const double EPS = 1e-10;
int main(){
    double a, b, c, d, e, f;
    cin >> a >> b >> c >> d >> e >> f;
    double t = f + c * c / (4 * a) + d * d / (4 * b) - e;
    t /= a;
    printf("%.10lf\n", sqrt(t));
}