Largest Rectangle Area

Given a set of coordinates on a 2D plane, your task is to compute the largest area of a rectangle whose sides are parallel to the axes. A rectangle is defined by four distinct points (x₁, y₁), (x₁, y₂), (x₂, y₁), and (x₂, y₂) such that all these points exist in the input. If no such rectangle can be formed, output 0.

The input first contains an integer n (the number of points). Each of the following n lines contains two integers representing the x and y coordinates of a point. The rectangle must have non-zero area. The area of a rectangle formed by two points (x₁, y₁) and (x₂, y₂) is computed as \( |x_2 - x_1| \times |y_2 - y_1| \).

Example:

Input:
4
1 1
1 3
3 1
3 3
Output:
4

</p>

inputFormat

The first line contains an integer n, which indicates the number of points. Each of the next n lines contains two space-separated integers representing the x and y coordinates of a point.

outputFormat

Output a single integer representing the largest rectangle area that can be formed with sides parallel to the axes. If no rectangle can be formed, output 0.

## sample

4
1 1
1 3
3 1
3 3

4