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;

namespace ITP1_10_A {
    class Program {
        static void Main(string[] args) {
            string[] s = Console.ReadLine().Split(' ');
            double x1 = double.Parse(s[0]), y1 = double.Parse(s[1]),
                   x2 = double.Parse(s[2]), y2 = double.Parse(s[3]);
            double distance = Math.Sqrt((x2 - x1) + (y2 - y1));
            Console.WriteLine(distance);
        }
    }
}