Problem: Everybody knows that the capital of Berland is connected to Bercouver (the Olympic capital) by a direct road. To improve the road's traffic capacity, there was placed just one traffic sign, limiting the maximum speed. Traffic signs in Berland are a bit peculiar, because they limit the speed only at that point on the road where they are placed. Right after passing the sign it is allowed to drive at any speed.

It is known that the car of an average Berland citizen has the acceleration (deceleration) speed of a km/h2, and has maximum speed of v km/h. The road has the length of l km, and the speed sign, limiting the speed to w km/h, is placed d km (1 ≤ d < l) away from the capital of Berland. The car has a zero speed at the beginning of the journey. Find the minimum time that an average Berland citizen will need to get from the capital to Bercouver, if he drives at the optimal speed.

The car can enter Bercouver at any speed.

Input

The first line of the input file contains two integer numbers a and v (1 ≤ a, v ≤ 10000). The second line contains three integer numbers l, d and w (2 ≤ l ≤ 10000; 1 ≤ d < l; 1 ≤ w ≤ 10000).

Output

Print the answer with at least five digits after the decimal point.

Examples

Input

1 1
2 1 3


Output

2.500000000000


Input

5 70
200 170 40


Output

8.965874696353

Solution (in JAVA):

Solution:
import java.io.*;
import java.util.*;

public class Main {

    public static void main(String[] args) throws IOException {
        InputStream inputStream = System.in;
        OutputStream outputStream = System.out;
        InputReader in = new InputReader(inputStream);
        PrintWriter out = new PrintWriter(outputStream);
        TaskB solver = new TaskB();
        solver.solve(in, out);
        out.close();
    }

    private static class TaskB {

        static final long max = 1000000000000000000L;
        static final double eps = 0.000001;
        static final long mod = 1000000007;
        static int N, M, K;
        static double A, V;

        void solve(InputReader in, PrintWriter out) throws IOException {

            double L, D, W;

            A = in.nextDouble();
            V = in.nextDouble();
            L = in.nextDouble();
            D = in.nextDouble();
            W = in.nextDouble();

            double time;

            if (W >= V) time = getTime(L, 0);
            else {
                double tw = W / A;
                double dw = dist(tw, 0);
                if (dw >= D) time = getTime(L, 0);
                else {
                    time = tw + 2 * getTime(0.5 * (D - dw), W) + getTime(L - D, W);
                }
            }

            System.out.printf("%.6f", time);
        }

        double getTime(double distance, double speed) {
            double D = 4 * speed * speed + 8 * A * distance;
            double timeAll = Math.max((-2 * speed - Math.sqrt(D)) / (2 * A), (-2 * speed + Math.sqrt(D)) / (2 * A));
            double timeMax = (V - speed) / A;
            if (timeAll <= timeMax) return timeAll;
            return (distance - dist(timeMax, speed)) / V + timeMax;
        }

        double dist(double time, double speed) {
            return speed * time + (A * time * time) / 2;
        }

        double segment(double x1, double y1, double x2, double y2) {
            return Math.sqrt((x1 - x2) * (x1 - x2) + (y1 - y2) * (y1 - y2));
        }

        long gcd(long a, long b) {
            if (b == 0) return a;
            return gcd(b, a % b);
        }

        long lcm(long a, long b) {
            return (a * b) / gcd(a, b);
        }

        boolean isPrime(long n) {
            if (n <= 1 || n > 3 && (n % 2 == 0 || n % 3 == 0))
                return false;
            for (long i = 5, j = 2; i * i <= n; i += j, j = 6 - j)
                if (n % i == 0)
                    return false;
            return true;
        }
    }

    private static class InputReader {
        StringTokenizer st;
        BufferedReader br;

        public InputReader(InputStream s) {
            br = new BufferedReader(new InputStreamReader(s));
        }

        public InputReader(FileReader s) throws FileNotFoundException {
            br = new BufferedReader(s);
        }

        public String next() {
            while (st == null || !st.hasMoreTokens())
                try {
                    st = new StringTokenizer(br.readLine());
                } catch (IOException e) {
                    throw new RuntimeException(e);
                }
            return st.nextToken();
        }

        public int nextInt() {
            return Integer.parseInt(next());
        }

        public long nextLong() {
            return Long.parseLong(next());
        }

        public String nextLine() {
            try {
                return br.readLine();
            } catch (IOException e) {
                throw new RuntimeException(e);
            }
        }

        public double nextDouble() {
            return Double.parseDouble(next());
        }

        public boolean ready() {
            try {
                return br.ready();
            } catch (IOException e) {
                throw new RuntimeException(e);
            }
        }
    }
}