#include <bits/stdc++.h>
#define rep(i,n) for (int i = 0; i < (int)(n); i ++)
#define irep(i,n) for (int i = (int)(n) - 1;i >= 0;--i)
using namespace std;
using ll = long long;
using PL = pair<ll,ll>;
using P = pair<int,int>;
constexpr int INF = 1000000000;
constexpr long long HINF = 100000'00000'00000'000;
constexpr long long MOD = 1000000007;// = 998244353;
constexpr double EPS = 1e-4;
constexpr double PI = 3.14159265358979;

int main() {
    cin.tie(nullptr);
    ios::sync_with_stdio(false);
    cout << setprecision(20);

    int a,b,c,d,e,f; cin >> a >> b >> c >> d >> e >> f;
    double r = sqrt((f - e)/a + (c*c + d*d)/(4*a*a));
    cout << r << '\n'; 
    return 0;
}