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문제

There are $N$ power sources, numbered from $1$ to $N$, scattered around the ICPC Kingdom. Power source $i$ is uniquely located at coordinate $(X_i , Y_i)$ in a 2D Cartesian plane such that there are no three power sources located in a straight line.

For each pair of distinct power sources $i$ and $j$ that satisfies $1 ≤ i < j ≤ N$, a magical barrier forms as a line segment that spans from $(X_i , Y_i)$ to $(X_j , Y_j )$.

You noticed a strange phenomenon. When two distinct magical barriers are intersecting, then both magical barriers are somewhat strengthened. To simplify things, you define the strength of a magical barrier $b$ as the number of magical barriers other than $b$ that intersects with $b$. Two distinct magical barriers are intersecting if and only if there exists exactly one point $(x, y)$ that lies on both magical barriers while none of the $N$ power sources are located at $(x, y)$.

You want to find the strength of the strongest magical barrier in the ICPC Kingdom.

입력

Input begins with an integer $N$ ($2 ≤ N ≤ 1000$) representing the number of power sources. Each of the next $N$ lines contains $2$ integers $X_i$ $Y_i$ ($-10^9 ≤ X_i , Y_i ≤ 10^9$) representing the location of power source $i$. It is guaranteed that the location of each power source is unique, and there are no three power sources located in a straight line.

출력

Output an integer in a single line representing the strength of the strongest magical barrier.

예제 입력 1

6
0 0
0 6
6 0
6 6
1 4
1 2

예제 출력 1

3

Let $⟨i, j⟩$ be the magical barrier that spans from power source $i$ to power source $j$.

One of the strongest magical barriers is $⟨1, 4⟩$ with a strength of $3$. The $3$ magical barriers that intersect with $⟨1, 4⟩$ are $⟨2, 3⟩$, $⟨3, 6⟩$, and $⟨3, 5⟩$. Note that the magical barrier $⟨2, 3⟩$ also has a strength of $3$.

예제 입력 2

2
0 0
0 1

예제 출력 2

0

The only magical barrier is $⟨1, 2⟩$ with a strength of $0$.

예제 입력 3

4
-3 0
3 0
0 3
0 1

예제 출력 3

0

All magical barriers have a strength of $0$.

예제 입력 4

4
0 0
0 1
1 0
1 1

예제 출력 4

1

The strongest magical barrier is either $⟨1, 4⟩$ or $⟨2, 3⟩$, which intersects each other at $(0.5, 0.5)$.