Time Limit: 1 Sec  Memory Limit: 128 MB
Submit: 6  Solved: 3
[Submit][Status][Web Board]

## Description

There are $$n$$ points in a two dimensions area. You can choose at most four points to enclose this area. Please output the maximum area that can be enclosed.

## Input

The first line is the integer n $$( 2 \leq n \leq 3000 )$$.

The following n lines each line contains 2 number $$x_i,y_i$$ $$(-600000 \leq x_i,y_i \leq 600000, 1 \leq i \leq n)$$.

## Output

One line a number, representing the maximum area. Keep the result to one decimal place.

## Sample Input

4
1.0 2.0
1.0 1.0
2.0 1.0
2.0 2.0

## Sample Output

1.0

[Submit][Status]