#include <bits/stdc++.h>
using namespace std;
char X[50][50];
int main() {
  short n, m;
  cin >> n >> m;
  int OK = 1;
  for (int i = 0; i < n; i++)
    for (int j = 0; j < m; j++) X[i][j] = '.';
  for (int i = 0; i < n; i++) {
    for (int j = 0; j < m; j++) {
      if (i % 2 == 0)
        X[i][j] = '#';
      else {
        if (j == 0 && OK % 2 == 0) {
          X[i][j] = '#';
          OK++;
          break;
        } else if (j == m - 1 && OK % 2 != 0) {
          X[i][j] = '#';
          OK++;
          break;
        }
      }
    }
  }
  for (int i = 0; i < n; i++) {
    for (int j = 0; j < m; j++) cout << X[i][j];
    cout << endl;
  }
  return 0;
}
