Problem: A car moves from point A to point B at speed v meters per second. The action takes place on the X-axis. At the distance d meters from A there are traffic lights. Starting from time 0, for the first g seconds the green light is on, then for the following r seconds the red light is on, then again the green light is on for the g seconds, and so on.

The car can be instantly accelerated from 0 to v and vice versa, can instantly slow down from the v to 0. Consider that it passes the traffic lights at the green light instantly. If the car approaches the traffic lights at the moment when the red light has just turned on, it doesn't have time to pass it. But if it approaches the traffic lights at the moment when the green light has just turned on, it can move. The car leaves point A at the time 0.

What is the minimum time for the car to get from point A to point B without breaking the traffic rules?

Input

The first line contains integers l, d, v, g, r (1 ≤ l, d, v, g, r ≤ 1000, d < l) — the distance between A and B (in meters), the distance from A to the traffic lights, car's speed, the duration of green light and the duration of red light.

Output

Output a single number — the minimum time that the car needs to get from point A to point B. Your output must have relative or absolute error less than 10 - 6.

Examples

Input

2 1 3 4 5


Output

0.66666667


Input

5 4 3 1 1


Output

2.33333333

Solution (in JAVA):

Solution:
import java.util.ArrayList;
import java.util.InputMismatchException;
import java.util.Locale;
import java.util.Scanner;
import java.util.regex.Pattern;

import java.io.OutputStreamWriter;
import java.io.PrintWriter;
import java.io.UnsupportedEncodingException;

public class Main {

	public static void main(String[] args) throws Exception {
        solve(1);	
    }
     
    public static void solve(int testCases) throws Exception{
    	
    	int l = StdIn.readInt();
    	int d = StdIn.readInt();
    	int v = StdIn.readInt();
    	int g = StdIn.readInt();
    	int r = StdIn.readInt();
    	
    	int d1 = d;
    	int d2 = l - d ;
    	double t = (double) d1 / v;
    	//StdOut.println("t = " + t);
    	double time = 0.0;
    	int count = 0;
    	while(t >= time){
    		if(count % 2 == 0){
    			time += g;
    			if(time > t){
    				break;
    			}
    			count++;
    		}else{
    			time += r;
    			if(time > t){
    				break;
    			}
    			count++;
    		}
    	}
    	if(count % 2 == 1){
    		t = time;
    	}	
    	//StdOut.println("t = " + t);
    	t = t + ((double) d2 / v);
    	StdOut.printf("%.6f\n", t);
    }      
    
}




final class StdIn {
 
    private StdIn() { }
 
    private static Scanner scanner;
    
    private static final String CHARSET_NAME = "UTF-8";
 
    private static final Locale LOCALE = Locale.US;
 
    private static final Pattern WHITESPACE_PATTERN = Pattern.compile("\\p{javaWhitespace}+");
 
    private static final Pattern EMPTY_PATTERN = Pattern.compile("");
 
    private static final Pattern EVERYTHING_PATTERN = Pattern.compile("\\A");
 
    public static boolean isEmpty() {
        return !scanner.hasNext();
    }
 
    public static boolean hasNextLine() {
        return scanner.hasNextLine();
    }
 
    public static boolean hasNextChar() {
        scanner.useDelimiter(EMPTY_PATTERN);
        boolean result = scanner.hasNext();
        scanner.useDelimiter(WHITESPACE_PATTERN);
        return result;
    }
 
    public static String readLine() {
        String line;
        try                 { line = scanner.nextLine(); }
        catch (Exception e) { line = null;               }
        return line;
    }
 
    public static char readChar() {
        scanner.useDelimiter(EMPTY_PATTERN);
        String ch = scanner.next();
        assert (ch.length() == 1) : "Internal (Std)In.readChar() error!"
            + " Please contact the authors.";
        scanner.useDelimiter(WHITESPACE_PATTERN);
        return ch.charAt(0);
    }  
 
 
    public static String readAll() {
        if (!scanner.hasNextLine())
            return "";
 
        String result = scanner.useDelimiter(EVERYTHING_PATTERN).next();
        // not that important to reset delimeter, since now scanner is empty
        scanner.useDelimiter(WHITESPACE_PATTERN); // but let's do it anyway
        return result;
    }
 
    public static String readString() {
        return scanner.next();
    }
 
    public static int readInt() {
        return scanner.nextInt();
    }
 
    public static double readDouble() {
        return scanner.nextDouble();
    }
 
    public static float readFloat() {
        return scanner.nextFloat();
    }
 
    public static long readLong() {
        return scanner.nextLong();
    }
    
    public static short readShort() {
        return scanner.nextShort();
    }
 
    public static byte readByte() {
        return scanner.nextByte();
    }
 
    public static boolean readBoolean() {
        String s = readString();
        if (s.equalsIgnoreCase("true"))  return true;
        if (s.equalsIgnoreCase("false")) return false;
        if (s.equals("1"))               return true;
        if (s.equals("0"))               return false;
        throw new InputMismatchException();
    }
 
    public static String[] readAllStrings() {
        // we could use readAll.trim().split(), but that's not consistent
        // because trim() uses characters 0x00..0x20 as whitespace
        String[] tokens = WHITESPACE_PATTERN.split(readAll());
        if (tokens.length == 0 || tokens[0].length() > 0)
            return tokens;
 
        // don't include first token if it is leading whitespace
        String[] decapitokens = new String[tokens.length-1];
        for (int i = 0; i < tokens.length - 1; i++)
            decapitokens[i] = tokens[i+1];
        return decapitokens;
    }
 
    public static String[] readAllLines() {
        ArrayList<String> lines = new ArrayList<String>();
        while (hasNextLine()) {
            lines.add(readLine());
        }
        return lines.toArray(new String[0]);
    }
 
    public static int[] readAllInts() {
        String[] fields = readAllStrings();
        int[] vals = new int[fields.length];
        for (int i = 0; i < fields.length; i++)
            vals[i] = Integer.parseInt(fields[i]);
        return vals;
    }
 
    public static double[] readAllDoubles() {
        String[] fields = readAllStrings();
        double[] vals = new double[fields.length];
        for (int i = 0; i < fields.length; i++)
            vals[i] = Double.parseDouble(fields[i]);
        return vals;
    }
    
    static {
        resync();
    }
 
    private static void resync() {
        setScanner(new Scanner(new java.io.BufferedInputStream(System.in), CHARSET_NAME));
    }
    
    private static void setScanner(Scanner scanner) {
        StdIn.scanner = scanner;
        StdIn.scanner.useLocale(LOCALE);
    }
 
    public static int[] readInts() {
        return readAllInts();
    }
 
    public static double[] readDoubles() {
        return readAllDoubles();
    }
 
    public static String[] readStrings() {
        return readAllStrings();
    }
 
}
 
final class StdOut {
 
    private static final String CHARSET_NAME = "UTF-8";
 
    private static final Locale LOCALE = Locale.US;
 
    private static PrintWriter out;
 
    static {
        try {
            out = new PrintWriter(new OutputStreamWriter(System.out, CHARSET_NAME), true);
        }
        catch (UnsupportedEncodingException e) { System.out.println(e); }
    }
 
    private StdOut() { }
 
    public static void close() {
        out.close();
    }
 
    public static void println() {
        out.println();
    }
 
    public static void println(Object x) {
        out.println(x);
    }
 
    public static void println(boolean x) {
        out.println(x);
    }
 
    public static void println(char x) {
        out.println(x);
    }
 
    public static void println(double x) {
        out.println(x);
    }
 
    public static void println(float x) {
        out.println(x);
    }
 
    public static void println(int x) {
        out.println(x);
    }
 
    public static void println(long x) {
        out.println(x);
    }
 
    public static void println(short x) {
        out.println(x);
    }
 
    public static void println(byte x) {
        out.println(x);
    }
 
    public static void print() {
        out.flush();
    }
 
    public static void print(Object x) {
        out.print(x);
        out.flush();
    }
 
    public static void print(boolean x) {
        out.print(x);
        out.flush();
    }
 
    public static void print(char x) {
        out.print(x);
        out.flush();
    }
 
    public static void print(double x) {
        out.print(x);
        out.flush();
    }
 
    public static void print(float x) {
        out.print(x);
        out.flush();
    }
 
    public static void print(int x) {
        out.print(x);
        out.flush();
    }
 
    public static void print(long x) {
        out.print(x);
        out.flush();
    }
 
    public static void print(short x) {
        out.print(x);
        out.flush();
    }
 
    public static void print(byte x) {
        out.print(x);
        out.flush();
    }
 
    public static void printf(String format, Object... args) {
        out.printf(LOCALE, format, args);
        out.flush();
    }
 
    public static void printf(Locale locale, String format, Object... args) {
        out.printf(locale, format, args);
        out.flush();
    }
 
}