#define _USE_MATH_DEFINES
#include <bits/stdc++.h>
using namespace std;
signed main() {
  ios::sync_with_stdio(false); cin.tie(0);
  int n, k;
  cin >> n >> k;
  int siz = (n + k * k - 1) / (k * k) * k;
  cout << siz << '\n';
  vector<vector<char>> ans(siz, vector<char>(siz, '.'));
  int cnt = 0;
  int row = 0, col = 0;
  while (cnt < n) {
    for (int i = 0; i < k; i++) {
      for (int j = 0; j < k; j++) {
        if (cnt++ < n) ans[row + i][col + j] = '#';
      }
    }
    row += k;
    col += k;
  }
  for (int i = 0; i < siz; i++) {
    for (int j = 0; j < siz; j++) {
      cout << ans[i][j];
    }
    cout << '\n';
  }
  return 0;
}