Problem:
Distance

Write a program which calculates the distance between two points P1(x1, y1) and P2(x2, y2).

Input

Four real numbers x1, y1, x2 and y2 are given in a line.

Output

Print the distance in real number. The output should not contain an absolute error greater than 10-4.

Sample Input

0 0 1 1

Sample Output

1.41421356

Solution in C# (judge verdict: Wrong Answer)

using System;

	public class Class1
	{
		public static void Main(String[] args)
		{
			string data=Console.ReadLine();
			string[] xxyy=data.Split();
			double x1=double.Parse(xxyy[0]);
			double x2=double.Parse(xxyy[1]);
			double y1=double.Parse(xxyy[2]);
			double y2=double.Parse(xxyy[3]);
			double a=x2-x1;
			double b=y2-y1;
			double c=a*a+b*b;
			Console.WriteLine(Math.Sqrt(c));
			
		}
	}