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: Accepted)

using System;

class MyClass
{
    public static void Main(string[] args)
    {
        var input = Console.ReadLine().Split();
        var x1 = double.Parse(input[0]);
        var y1 = double.Parse(input[1]);
        var x2 = double.Parse(input[2]);
        var y2 = double.Parse(input[3]);
        var d = Math.Sqrt((x1 - x2) * (x1 - x2) + (y1 - y2) * (y1 - y2));
        Console.WriteLine(d.ToString("F8"));
    }
}