macro_rules! input {
    (source = $s:expr, $($r:tt)*) => {
        let mut iter = $s.split_whitespace();
        input_inner!{iter, $($r)*}
    };
    ($($r:tt)*) => {
        let mut s = {
            use std::io::Read;
            let mut s = String::new();
            std::io::stdin().read_to_string(&mut s).unwrap();
            s
        };
        let mut iter = s.split_whitespace();
        input_inner!{iter, $($r)*}
    };
}

macro_rules! input_inner {
    ($iter:expr) => {};
    ($iter:expr, ) => {};

    ($iter:expr, $var:ident : $t:tt $($r:tt)*) => {
        let $var = read_value!($iter, $t);
        input_inner!{$iter $($r)*}
    };
}

macro_rules! read_value {
    ($iter:expr, ( $($t:tt),* )) => {
        ( $(read_value!($iter, $t)),* )
    };

    ($iter:expr, [ $t:tt ; $len:expr ]) => {
        (0..$len).map(|_| read_value!($iter, $t)).collect::<Vec<_>>()
    };

    ($iter:expr, chars) => {
        read_value!($iter, String).chars().collect::<Vec<char>>()
    };

    ($iter:expr, usize1) => {
        read_value!($iter, usize) - 1
    };

    ($iter:expr, $t:ty) => {
        $iter.next().unwrap().parse::<$t>().expect("Parse error")
    };
}

pub trait ChangeMinMax {
    fn change_min(&mut self, v: Self) -> bool;
    fn change_max(&mut self, v: Self) -> bool;
}

impl<T: PartialOrd> ChangeMinMax for T {
    fn change_min(&mut self, v: T) -> bool {
        *self > v && {
            *self = v;
            true
        }
    }

    fn change_max(&mut self, v: T) -> bool {
        *self < v && {
            *self = v;
            true
        }
    }
}

struct Input {
    n: usize,
    cards: Vec<(u64, u64)>,
}

impl Input {
    fn read_input() -> Self {
        input! {
            n: usize,
            cards: [(u64, u64); n],
        }

        Input { n, cards }
    }
}

fn main() {
    let input = Input::read_input();
    let mut outputs = vec![];
    let mut cards = input.cards.clone();

    for _ in 0..45 {
        let mut best_i = 1;
        let mut best_error = u128::max_value();

        for i in 1..input.n {
            let a = (cards[0].0 + cards[i].0) / 2;
            let b = (cards[0].1 + cards[i].1) / 2;

            let error0 = a.abs_diff(500_000_000_000_000_000) as u128;
            let error1 = b.abs_diff(500_000_000_000_000_000) as u128;

            if best_error.change_min(error0 * error0 + error1 * error1) {
                best_i = i;
            }
        }

        outputs.push((0, best_i));
        let a = (cards[0].0 + cards[best_i].0) / 2;
        let b = (cards[0].1 + cards[best_i].1) / 2;
        cards[0] = (a, b);
        cards[best_i] = (a, b);
    }

    println!("{}", outputs.len());

    for (a, b) in outputs {
        println!("{} {}", a + 1, b + 1);
    }
}