Description

Given three points of a rectangle, calculate the perimeter of it.

Input

There are multiple test cases.

In each case, three integer coordinates are given to describe the rectangle, i.e. (x1, y1), (x2, y2), (x3, y3).

0 <= x1, y1, x2, y2, x3, y3 <= 10000.

Output

Output the perimeter of the rectangle corresponding to each test case.

The result should be accurated to three decimal places.

0 0 2 1 2 0
1 1 0 2 2 4

6.000
8.485