Making chocolate chip cookies involves mixing flour, salt, oil, baking soda and chocolate chips to form dough which is rolled into a plane. Circles are cut from the plane, placed on a cookie sheet, and baked in an oven for about twenty minutes. When the cookies are done, they are removed from the oven and allowed to cool before being eaten.</p>

We are concerned here with the process of cutting a single round cookie that contains all the chocolate chips. Once the dough has been rolled, each chip is visible in the planar dough, so we need simply to find a cookie cutter big enough to circle all the chips. What is the diameter of the smallest possible round cookie containing all the chips?

입력 형식

Input consists of a positive integer $n$ not greater than $10$, followed by $n$ lines of input. Each line gives the coordinates of one chocolate chip on the plane. Each coordinate is an integer in the range $[0, 1000]$.

출력 형식

Output consists of a single real number, the diameter of the cookie rounded to two decimal places.

예제 입력 1

4
1 1
1 0
0 1
0 0

예제 출력 1

1.41

예제 입력 2

3
1 1
10 0
0 0

예제 출력 2

10.00