Problem:
Score : 300 points

Problem Statement

There are N balls in a two-dimensional plane. The i-th ball is at coordinates (x_i, y_i).

We will collect all of these balls, by choosing two integers p and q such that p \neq 0 or q \neq 0 and then repeating the following operation:

Choose a ball remaining in the plane and collect it. Let (a, b) be the coordinates of this ball. If we collected a ball at coordinates (a - p, b - q) in the previous operation, the cost of this operation is 0. Otherwise, including when this is the first time to do this operation, the cost of this operation is 1.

Find the minimum total cost required to collect all the balls when we optimally choose p and q.

Constraints

1 \leq N \leq 50

|x_i|, |y_i| \leq 10^9

If i \neq j, x_i \neq x_j or y_i \neq y_j.

All values in input are integers.

Input

Input is given from Standard Input in the following format:

N
x_1 y_1
:
x_N y_N

Output

Print the minimum total cost required to collect all the balls.

Sample Input 1

2
1 1
2 2

Sample Output 1

1

If we choose p = 1, q = 1, we can collect all the balls at a cost of 1 by collecting them in the order (1, 1), (2, 2).

Sample Input 2

3
1 4
4 6
7 8

Sample Output 2

1

If we choose p = -3, q = -2, we can collect all the balls at a cost of 1 by collecting them in the order (7, 8), (4, 6), (1, 4).

Sample Input 3

4
1 1
1 2
2 1
2 2

Sample Output 3

2

Solution in Rust (1.15.1) (judge verdict: Wrong Answer)

use std::io::*;

const SP: u8 = b' ';
const LF: u8 = b'\n';

struct CharacterInput<'a> {
    locked_stdin: StdinLock<'a>,
    bytes_buffer: Vec<u8>,
}

impl<'a> CharacterInput<'a> {
    fn read(&mut self, delimiter: u8) -> &[u8] {
        self.bytes_buffer.clear();

        let mut len = self
            .locked_stdin
            .read_until(delimiter, &mut self.bytes_buffer)
            .unwrap();

        if len > 0 {
            len -= 1;
        }

        &self.bytes_buffer[0..len]
    }

    fn scan_u(&mut self, delimiter: u8) -> u32 {
        self.read(delimiter)
            .into_iter()
            .fold(0, |accumulator, byte| {
                (byte - b'0') as u32 + accumulator * 10
            })
    }
}

fn create_cin<'a>(input: StdinLock<'a>, buffer_capacity: usize) -> CharacterInput {
    CharacterInput {
        locked_stdin: input,
        bytes_buffer: Vec::with_capacity(buffer_capacity),
    }
}

fn println<T: std::string::ToString>(s: T) {
    println!("{}", s.to_string());
}

// ------------------------------------------------------------------------

type Pos = (i32, i32);

use std::collections::HashMap;

fn main() {
    let cin = stdin();
    let cin = &mut create_cin(cin.lock(), 64);

    let n = cin.scan_u(LF) as usize;

    let mut ball_list: Vec<Pos> = Vec::with_capacity(n);

    for _ in 0..n {
        ball_list.push((cin.scan_u(SP) as i32, cin.scan_u(LF) as i32));
    }

    let mut pos_diff_list: HashMap<Pos, usize> = HashMap::with_capacity(n * n);

    for i in 0..n - 1 {
        let ball = ball_list[i];

        for k in i + 1..n {
            let other_ball = ball_list[k];
            let pos_diff = if other_ball.0 > ball.0 {
                (other_ball.0 - ball.0, other_ball.1 - ball.1)
            } else {
                (ball.0 - other_ball.0, ball.1 - other_ball.1)
            };
            // println!("({}, {})", pos_diff.0, pos_diff.1);

            let count = pos_diff_list.entry(pos_diff).or_insert(0);
            *count += 1;
        }
    }

    let mut cost = 0;
    let mut remaining_count: usize = n;

    let mut count_list: Vec<usize> = pos_diff_list.values().map(|&v| v).collect();
    count_list.sort();

    for count in count_list.into_iter().rev() {
        if remaining_count < count { break; }
        remaining_count -= count;
        // println!("count: {}, remaining: {}", count, remaining_count);
        cost += 1;
    }

    println(cost);
}