/**
 * code generated by JHelper
 * More info: https://github.com/AlexeyDmitriev/JHelper
 * @author
 */

#include <iostream>
#include <fstream>

#ifndef SOLUTION_COMMON_H

#include <bits/stdc++.h>

using namespace std;

using ll = long long;
using PI = pair<int, int>;
template<class T> using V = vector<T>;
using VI = V<int>;
#define _1 first
#define _2 second

#ifdef MY_DEBUG
# define DEBUG(x) x
#else
# define DEBUG(x)
#endif

template<class T>
inline void debug(T &A) {
  DEBUG(
      for (const auto &a : A) {
        cerr << a << " ";
      }
      cerr << '\n';
  )
}

template<class T, class Func>
inline void debug_with_format(T &A, Func f) {
  DEBUG(
      for (const auto &a : A) {
        cerr << f(a) << " ";
      }
      cerr << '\n';
  )
}

template<class T>
inline void debug_dim2(T &A) {
  DEBUG(
      for (const auto &as : A) {
        debug(as);
      }
  )
}

template<typename ... Args>
inline void debug(const char *format, Args const &... args) {
  DEBUG(
      fprintf(stderr, format, args ...);
      cerr << '\n';
  )
}

template<typename ... Args>
string format(const string &fmt, Args ... args) {
  size_t len = snprintf(nullptr, 0, fmt.c_str(), args ...);
  vector<char> buf(len + 1);
  snprintf(&buf[0], len + 1, fmt.c_str(), args ...);
  return string(&buf[0], &buf[0] + len);
}

template<class T1, class T2>
string fmtP(pair<T1, T2> a) {
  stringstream ss;
  ss << "(" << a._1 << "," << a._2 << ")";
  return ss.str();
}

#define SOLUTION_COMMON_H

#endif //SOLUTION_COMMON_H

const int MOD = 1000000007;

class B {
public:
  void solve(std::istream& in, std::ostream& out) {
    int N, K;
    in >> N >> K;
    int a = K * K;
    int b = N / a;
    int remain = N % a;
    int c = 0;
    while(c * c < remain) c++;
    int m = c + K * b;

    debug("%d %d %d %d", remain, b, c, m);

    V<V<char>> g(m, V<char>(m, '.'));
    for (int i = 0; i < b; ++i) {
      for (int j = 0; j < K; ++j) {
        for (int k = 0; k < K; ++k) {
//          debug("%d %d %d", i, j, k);
          g[i * K + j][i * K + k] = '#';
        }
      }
    }
    for (int i = 0; i < c; ++i) {
      for (int j = 0; j < c; ++j) {
        if (remain-- > 0) g[b * K + i][b * K + j] = '#';
      }
    }

    out << m << '\n';
    for (int i = 0; i < m; ++i) {
      for (int j = 0; j < m; ++j) {
        out << g[i][j];
      }
      out << '\n';
    }
  }
};


int main() {
	B solver;
	std::istream& in(std::cin);
	std::ostream& out(std::cout);
	solver.solve(in, out);
	return 0;
}