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 Scala (judge verdict: Accepted)

object Main {
  def main(args: Array[String]): Unit = {
    val Array(x1, y1, x2, y2, _*) = io.StdIn.readLine().split(" ").map(_.toDouble)

    val dx = Math.abs(x2 - x1)
    val dy = Math.abs(y2 - y1)
    val d = Math.sqrt(dx * dx + dy * dy)
    println(f"$d%.8f")
  }
}