#define _USE_MATH_DEFINES #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include typedef long long int ll; //#include using namespace std; ll gcd(ll a, ll b) { if (a < b)swap(a, b); if (b == 0)return a; return gcd(b, a % b); } int lcm(int a, int b) { return a * b / gcd(a, b); } int main() { int Q; Q = 1; //cin >> Q; while (Q--) { double a, b, c, d, e, f; cin >> a >> b >> c >> d >> e >> f; f -= e; f /= a; c /= a; d /= a; f += (c * c + d * d) / 4; cout << setprecision(12); cout << sqrt(f); } return 0; }