/* package whatever; // don't place package name! */
 
import java.util.*;
import java.lang.*;
import java.io.*;
 
/* Name of the class has to be "Main" only if the class is public. */
class Ideone
{
	public static void main (String[] args) throws java.lang.Exception
	{
		Scanner sc = new Scanner(System.in);
		int x, y, A, B, C;
		x = sc.nextInt();
		y = sc.nextInt();
		A = sc.nextInt();
		B = sc.nextInt();
		C = sc.nextInt();
 
		double res = Math.abs(A*x + B*y + C)/Math.sqrt(A*A + B*B);
		System.out.printf("%.6f",res);
 
	}
}

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MSAxIDEgMSAtMQ==

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