#include <bits/stdc++.h>
using namespace std;
template <typename T> bool chmax(T &u, const T z) { if (u < z) {u = z; return true;} else return false; }
template <typename T> bool chmin(T &u, const T z) { if (u > z) {u = z; return true;} else return false; }
#define rep(i, n) for (int i = 0; i < (int)(n); i++)
#define ll long long 

int main(){
	double a,b,c,d,e,f;
	cin>>a>>b>>c>>d>>e>>f;
	double r;
	r=sqrt(f-e+(c*c)/((double)4*a*a)+(d*d)/((double)4*b*b));
	cout<<fixed<<setprecision(12)<<r<<endl;
	return 0;
}