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.StreamTokenizer;
import java.io.InputStreamReader;
import java.io.IOException;
import java.io.BufferedReader;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.io.Reader;
import java.io.InputStream;

/**
 * Built using CHelper plug-in
 * Actual solution is at the top
 */
public class Main {
	public static void main(String[] args) {
		InputStream inputStream = System.in;
		OutputStream outputStream = System.out;
		TokenizerReader in = new TokenizerReader(inputStream);
		PrintWriter out = new PrintWriter(outputStream);
		TaskD solver = new TaskD();
		solver.solve(1, in, out);
		out.close();
	}
}

class TaskD {
    public void solve(@SuppressWarnings("UnusedParameters") int testNumber, TokenizerReader in, PrintWriter out) {
        int a = in.nextInt(), v = in.nextInt();
        int l = in.nextInt(), d = in.nextInt(), w = in.nextInt();
        Pair<Double> firstPart = calcFirstPart(a, v, w, d);
        double t1 = firstPart.first, u = firstPart.second;
        double t2 = calcSecondPart(a, v, u, l-d);
        out.printf("%.12f", t1+t2);
    }

    private Pair<Double> calcFirstPart(double a, double v, double w, double d) {
        if (v <= w || w * w / 2.0 / a > d) {
            double t = calcSecondPart(a, v, 0, d);
            return new Pair<>(t, Math.min(t*a, v));
        }
        double t = Math.sqrt(d /a + w * w / 2.0 / a / a);
        if (t * a < v)
            return new Pair<>(2*t - w / a, (double)w);
        double t1 = v / a;
        double s1 = t1 * v / 2;
        double t3 = (v - w) / a;
        double s3 = (v + w) * t3 / 2;
        double s2 = d - s1 - s3;
        assert s2 > -1e-5;
        double t2 = s2 / v;
        return new Pair<>(t1 + t2 + t3, w);
    }

    private double calcSecondPart(double a, double v, double u, double l) {
        double timeUntilMaxSpeed = (v-u)/a;
        double distUntilMaxSpeed = (v+u)*timeUntilMaxSpeed/2.0;
        if (distUntilMaxSpeed < l)
            return timeUntilMaxSpeed + (l - distUntilMaxSpeed) / v;
        else
            return (Math.sqrt(u*u + 2.0*a*l) - u) / a;
    }
}

class TokenizerReader extends StreamTokenizer {
    public TokenizerReader(InputStream in) {
        super(new BufferedReader(new InputStreamReader(in)));
        defaultConfig();
    }

    public String nextString() {
        try {
            nextToken();
        } catch (IOException e) {
            throw new RuntimeException("nextString: exception in line " + lineno(), e);
        }
        return sval;
    }

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

    public void defaultConfig() {
        resetSyntax();
        wordChars(33, 126);
        whitespaceChars(0, ' ');
    }

}

class Pair<T> {
    public final T first, second;

    public Pair(T first, T second) {
        this.first = first;
        this.second = second;
    }

    public int hashCode() {
        return first.hashCode() * 31013 + second.hashCode();
    }

    public boolean equals(Object obj) {
        Pair<T> p = (Pair<T>) obj;
        return first.equals(p.first) && second.equals(p.second);
    }
}