#include <iostream>

const int MMAX=1000;
int map[MMAX][MMAX];

int main() {
  int N, K;
  std::cin >> N >> K;
  int m=0;
  while (m*K<N) ++m;
  std::cout << m << std::endl;
  for (int i=0;i<m;++i) for (int j=0;j<m;++j) map[i][j]=0;
  for (int i=0;i<m;++i) {
    for (int j=0;j<2*m;++j) {
      if (i<=j&&j<i+K) {
        map[i][j%m]=1;
      }
    }
  }
  for (int i=0;i<m;++i) {
    for (int j=0;j<m;++j) {
      if (map[i][j]==1) std::cout << "#";
      else std::cout << ".";
    }
    std::cout << std::endl;
  }
}