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 Aizu
{
    class OnlineJudge
    {
        public static void Main()
        {
            var v = Console.ReadLine().Split();
            var p = new double[6];
            for(int i=0; i < 4; p[i] = double.Parse(v[i++])) ;
            Console.WriteLine("{0:f5}", Math.Sqrt((p[4] = p[0] - p[2]) * p[4] + (p[5] = p[1] - p[3]) * p[5]));
        }
    }
}