import java.awt.*;
import java.io.*;
import java.util.ArrayList;
import java.util.StringTokenizer;
import java.util.stream.IntStream;

public class D_CanYouDrawACircle {
    private static final BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
    private static final PrintWriter pw = new PrintWriter(new BufferedWriter(new OutputStreamWriter(System.out)));
    private static StringTokenizer st;

    private static int readInt() throws IOException {
        while (st == null || !st.hasMoreTokens()) st = new StringTokenizer(br.readLine());
        return Integer.parseInt(st.nextToken());
    }

    public static void main(String[] args) throws IOException {
        solve();
        pw.close();
    }

    private static void solve() throws IOException {
        double a = readInt();
        double b = readInt();
        double c = readInt();
        double d = readInt();
        double e = readInt();
        double f = readInt();

        assert a == b;
        // a x 2 + b y 2 + c x + d y + e = f
        // r * r = (f-e-4 * c * c/a - 4 * d * d/b)/a
        double r = Math.sqrt((f - e + c * c / a / 4 + d * d / b / 4) / a);
        // wrong?!
        pw.printf("%.5f\n", r);
    }

}