Fence Orthogonality

Evil bunnies are eating Freddyâ€™s vegetables. In order to stop them, he decided to build a fence enclosing all vegetables in his garden. Freddy wants the fence to be as cheap (i.e., short) as possible, but for technical reasons, he can only build rectangular fences. For simplicity, we will assume the vegetables are negligibly small and can be represented by points in a two-dimensional plane.

The input consists of several test cases, at most 50.

The first line of each test case contains one integer
$N$ ($3\le N\le 10\, 000$) giving the
number of vegetables in the garden. Each of the following
$N$ lines contains two
integers $X_ i$ and
$Y_ i$ ($0\le X_ i, Y_ i\le 10\, 000$), giving
the coordinates of one vegetable to be protected. No two
vegetables have the same coordinates. You may also assume the
vegetables are not *all* on the same straight line.

For each test case, output a single line containing one real number $t$, giving the smallest length of the perimeter of a rectangular fence enclosing all the vegetables. Note that the edges of the rectangle do not need to be parallel with the coordinate axes.

The answer will be accepted as correct if the difference between $t$ and the exact answer is at most $0.0005$.

Sample Input 1 | Sample Output 1 |
---|---|

3 0 0 1 0 0 1 3 10 0 0 10 4 4 4 1 0 0 1 2 1 1 2 |
4 31.112698 5.656854 |