Problem Statement

We have $N$ points in a two-dimensional plane. The coordinates of the $i$-th point $(1 \leq i \leq N)$ are $(x_i,y_i)$. Let us consider a rectangle whose sides are parallel to the coordinate axes that contains $K$ or more of the $N$ points in its interior. Here, points on the sides of the rectangle are considered to be in the interior. Find the minimum possible area of such a rectangle.

Constraints

• $2 \leq K \leq N \leq 50$
• $-10^9 \leq x_i,y_i \leq 10^9 (1 \leq i \leq N)$
• $x_i≠x_j (1 \leq i<j \leq N)$
• $y_i≠y_j (1 \leq i<j \leq N)$
• All input values are integers. (Added at 21:50 JST)

Input

Input is given from Standard Input in the following format:

N K
x_1 y_1
:
x_{N} y_{N}

Output

Print the minimum possible area of a rectangle that satisfies the condition.