use std::io::*;

fn main() {
    let mut s: String = String::new();
    std::io::stdin().read_to_string(&mut s).ok();
    let mut itr = s.trim().split_whitespace();
    let n: usize = itr.next().unwrap().parse().unwrap();
    let k: usize = itr.next().unwrap().parse().unwrap();

    let m = (n + k * k - 1) / (k * k) * k;
    let mut ans: Vec<Vec<char>> = vec![vec!['.'; m]; m];

    let mut a = 0;
    let mut b = 0;
    'out: loop {
        for i in k * a..k * a + k {
            for j in k * a..k * a + k {
                ans[i][j] = '#';
                b += 1;
                if b == n {
                    break 'out;
                }
            }
        }
        a += 1;
    }

    let mut out = Vec::new();
    writeln!(out, "{}", m).ok();
    for i in 0..m {
        let s: String = ans[i].clone().into_iter().collect();
        writeln!(out, "{}", s).ok();
    }
    stdout().write_all(&out).unwrap();
}