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;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace _1_10_a
{
    class Program
    {
        static void Main(string[] args)
        {
            string[] s = Console.ReadLine().Split(' ');
            double x1 = double.Parse(s[0]);
            double y1 = double.Parse(s[1]);
            double x2 = double.Parse(s[2]);
            double y2 = double.Parse(s[3]);
            double answer = 0;

            double a = x2 - x1;
            double b = y2 - y1;

            answer = Math.Sqrt(a * a + b * b);

            Console.WriteLine(answer);
        }
    }
}