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;

namespace AizuOnLine
{
    class Program
    {
        static void Main(string[] args)
        {
            string[] data = Console.ReadLine().Split(' ');
            double x1 = double.Parse(data[0]);
            double y1 = double.Parse(data[1]);
            double x2 = double.Parse(data[2]);
            double y2 = double.Parse(data[3]);

            double ans = Math.Sqrt((x2 - x1) * (x2 - x1) + (y2 - y1) * (y2 - y1));

            Console.WriteLine(ans.ToString("F8"));
        }
    }
}