Inhabitants of the Wonderland have decided to hold a regional
programming contest. The Judging Committee has volunteered and
has promised to organize the most honest contest ever. It was decided
to connect computers for the contestants using a “star” topology - i.e. connect them all to a single central hub. To organize a truly honest contest, the Head of the Judging Committee has decreed to place all contestants evenly around the hub on an equal distance
from it.

To buy network cables, the Judging Committee has contacted a local network solutions provider with a request to sell for them a
specified number of cables with equal lengths. The Judging
Committee wants the cables to be as long as possible to sit
contestants as far from each other as possible.

The Cable Master of the company was assigned to the task. He knows the length of each cable in the stock up to a centimeter, and he can cut them with a centimeter precision being told the length of the pieces he must cut. However, this time, the length is not known
and the Cable Master is completely puzzled.

You are to help the Cable Master, by writing a program that will
determine the maximal possible length of a cable piece that can be
cut from the cables in the stock, to get the specified number of
pieces.

### Input

The first line contains two integers N and K, separated by a space. N (1 ≤ N ≤ 10000) is the number of cables in the stock, and K
(1 ≤ K ≤ 10000) is the number of requested pieces. The first line is followed by N lines with one number per line, that specify the length of each cable in the stock in meters. All cables are at least 1 meter and at most 100 kilometers in length. All lengths are written with a centimeter precision, with exactly two digits after a decimal point.

### Output

Write the maximal length (in meters) of the pieces that Cable
Master may cut from the cables in the stock to get the requested number of pieces. The number must be written with a centimeter precision, with exactly two digits after a decimal point.

If it is not possible to cut the requested number of pieces each one being at least one centimeter long, then the output must contain the single number “0.00” (without quotes).

### Sample

input | output |
---|

4 11
8.02
7.43
4.57
5.39 | 2.00 |

**Problem Author: **Vladimir Pinaev, Roman Elizarov

**Problem Source: **2001-2002 ACM Northeastern European Regional Programming Contest