package main

import (
	"bufio"
	"fmt"
	"os"
	"sort"
	"strconv"
)

func out(x ...interface{}) {
	fmt.Println(x...)
}

var sc = bufio.NewScanner(os.Stdin)

func getInt() int {
	sc.Scan()
	i, e := strconv.Atoi(sc.Text())
	if e != nil {
		panic(e)
	}
	return i
}

func getInts(N int) []int {
	ret := make([]int, N)
	for i := 0; i < N; i++ {
		ret[i] = getInt()
	}
	return ret
}

func getString() string {
	sc.Scan()
	return sc.Text()
}

// min, max, asub, absなど基本関数
func max(a, b int) int {
	if a > b {
		return a
	}
	return b
}

func min(a, b int) int {
	if a < b {
		return a
	}
	return b
}

func asub(a, b int) int {
	if a > b {
		return a - b
	}
	return b - a
}

func abs(a int) int {
	if a >= 0 {
		return a
	}
	return -a
}

func lowerBound(a []int, x int) int {
	idx := sort.Search(len(a), func(i int) bool {
		return a[i] >= x
	})
	return idx
}

func upperBound(a []int, x int) int {
	idx := sort.Search(len(a), func(i int) bool {
		return a[i] > x
	})
	return idx
}

func f(K, N int) {
	n := 1
	for {
		if n*n >= N {
			break
		}
		n++
	}
	out(n)
	for i := 0; i < n; i++ {
		for j := 0; j < n; j++ {
			if N != 0 {
				fmt.Print("#")
				N--
			} else {
				fmt.Print(".")
			}
		}
		out()
	}
}

func fill(a [][]byte, x, y, n, m int) {
	for i := 0; i < n; i++ {
		for j := 0; j < n; j++ {
			if m != 0 {
				a[y+i][x+j] = '#'
				m--
			}
		}
	}
}

func main() {
	sc.Split(bufio.ScanWords)
	N, K := getInt(), getInt()

	a := make([][]byte, 1000)
	for i := 0; i < N; i++ {
		a[i] = make([]byte, 1000)
		for j := 0; j < N; j++ {
			a[i][j] = '.'
		}
	}

	x, y := 0, 0
	for N != 0 {
		if N >= K*K {
			fill(a, x, y, K, K*K)
			N -= K * K
			x += K
			y += K
			continue
		}
		n := 1
		for {
			if n*n >= N {
				break
			}
			n++
		}
		fill(a, x, y, n, N)
		x += n
		y += n
		break
	}

	out(y)
	for i := 0; i < y; i++ {
		out(string(a[i][:x]))
	}
}