#include <bits/stdc++.h>
using namespace std;

int main()
{
	double a, b, c, d, e, f;
	cin >> a >> b >> c >> d >> e >> f;
	
	cout << setprecision(16) << sqrt(f - e + c * c / (4 * a) + d * d / (4 * b)) << endl;
	return 0;
}