use proconio::input;
use proconio::fastout;

#[fastout]
#[allow(non_snake_case)]
fn main() {
    input! {
        mut X: usize,
    }
    assert!(1 <= X && X <= 1_000_000_000_000_000_000);
    if X == 1 {
        println!("2");
        println!("1 2");
        println!("b g");
        return;
    }
    let n = (X as f64).sqrt() as usize;
    let mut p = Vec::new();
    while X % 4 == 0 {
        p.push(4);
        X /= 4;
    }
    for i in 2..=n {
        if i >= 200000 {
            if X == 1 {
                break;
            }
            println!("-1");
            return;
        }
        while X % i == 0 {
            p.push(i);
            X /= i;
        }
    }
    if X > 1 {
        p.push(X);
    }
    let N = p.len();
    let s = p.iter().sum::<usize>();
    if N + s > 200_000 {
        println!("-1");
        return;
    }
    println!("{}", N + s);
    let mut j = N;
    for i in 0..N {
        for _ in 0..p[i] {
            println!("{} {}", i+1, j+1);
            j += 1;
        }
        if i < N - 1 {
            println!("{} {}", i+1, i+2);
        }
    }
    println!("{} {}", "b".repeat(N).chars().map(|x| x.to_string()).collect::<Vec<String>>().join(" "), "g".repeat(s).chars().map(|x| x.to_string()).collect::<Vec<String>>().join(" "));
}