#include <bits/stdc++.h>
using namespace std;
int a, b, c, d, t, g;
int main() {
  cin >> a >> b;
  g = b;
  for (c = 1; c <= a; c++) {
    if (c % 2 == 1) {
      while (b > 0) {
        if (b > 1) cout << "#";
        if (b == 1) cout << "#" << endl;
        b--;
        d++;
      }
      b = d;
      d = 0;
    }
    if (c % 4 == 2) {
      while (b > 0) {
        if (b > 1) cout << ".";
        if (b == 1) cout << "#" << endl;
        b--;
        d++;
      }
      b = d;
      d = 0;
    }
    if (c % 4 == 0) {
      while (b > 0) {
        t++;
        if (t == 1) cout << "#";
        if (t > 1 && t < g) cout << ".";
        if (t == g) cout << "." << endl;
        b--;
        d++;
      }
      b = d;
      d = 0;
      t = 0;
    }
  }
}
