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.util.*;
import java.io.*;
import java.math.*;
public class Solution{
    static double a,v;
	public static void main(String[] args) throws Exception {
		a=nextInt();
        v=nextInt();
        double l=nextInt();
        double d=nextInt();
        double w=nextInt();
        double ans=0;
        double tw=w/a;
        double dw=distance(0,tw);
        // if(v<=w || d<=dw)
        //     ans=time(0,l);
        // else
        //     ans=tw + 2 * time(w,(d-dw)/2) + time(l-d,w);
        // System.out.printf("%.10g%n",ans);
        double totalTime = 0.0;
        if (v >= w) {
            if (w*w >= 2*a*d) {
                double x = Math.sqrt(2*a*d);
                totalTime = x / a;
                if ((v*v-x*x) >= 2*a*(l-d))
                    totalTime += (-2*x+Math.sqrt(4*x*x+8*a*(l-d))) / (2*a);
                else
                    totalTime += (v-x)/(1.0*a) + (l-d-(v*v-x*x)/(2.0*a))/v;
            } else {
                if (2*v*v-w*w <= 2*a*d) {
                    totalTime = v / (1.0*a) + (v-w) / (1.0*a) + (d-(2*v*v-w*w)/(2.0*a)) / v;
                } else {
                    double x = Math.sqrt((2*a*d+w*w)/2.0);
                    totalTime = x / a + (x-w) / a;
                }
                if ((v*v-w*w) >= 2*a*(l-d))
                    totalTime += (-2*w+Math.sqrt(4*w*w+8*a*(l-d))) / (2*a);
                else
                    totalTime += (v-w)/(1.0*a) + (l-d-(v*v-w*w)/(2.0*a))/v;
            }
        } else {
            if (v*v >= 2*a*l)
                totalTime = Math.sqrt(l*2.0/a);
            else
                totalTime = v / (1.0*a) + (l-v*v/(2.0*a)) / v;
        }
        System.out.printf("%.10g%n",totalTime);
	}
    static double distance(double u,double t){
        return u*t+a*t*t/2;
    }
    static double time(double u,double s){
        //0.5a tt + u t - s = 0
        double d= u*u+2*a*s;
        d=Math.sqrt(d);
        double t1 = (d-u)/a;
        double t2 = (v-u)/a;
        if(t2>=t1)
            return t1;
        t2 += (s - distance(u,t2))/v;   
        return t2;
    }
	static int nextInt()throws IOException{
		InputStream in=System.in;
        int ans=0;
        boolean flag=true;
        byte b=0;
        while ((b>47 && b<58) || flag){
            if(b>=48 && b<58){
                ans=ans*10+(b-48);
                flag=false;
            }
            b=(byte)in.read();
        }
        return ans;
    }
    static String next()throws Exception{
    	StringBuilder sb=new StringBuilder(1<<16);
    	InputStream in=System.in;
    	byte b=0;
    	do{
    		if(!isWhiteSpace(b))
    			sb.append((char)b);
    		b=(byte)in.read();
    	}while(!isWhiteSpace(b) || sb.length()==0);
    	return sb.toString();
    }
    static boolean isWhiteSpace(byte b){
    	char ch=(char)b;
    	return ch=='\0' || ch==' ' || ch=='\n';
    }
}