#include <bits/stdc++.h>
using namespace std;
long long mod = (long long)1e9 + 7;
const long long INF = (long long)1e18;
long long power(long long a, long long b) {
  long long ret = 1;
  while (b) {
    if (b & 1) ret *= a;
    a *= a;
    if (ret >= mod) ret %= mod;
    if (a >= mod) a %= mod;
    b >>= 1;
  }
  return ret;
}
long long inv(long long x) { return power(x, mod - 2); }
int main() {
  ios_base::sync_with_stdio(false);
  long long n, m, flag = 0;
  cin >> n >> m;
  for (long long i = 0; i < n; i++) {
    if (i % 2 == 0) {
      for (long long j = 0; j < m; j++) cout << "#";
    } else {
      if (flag == 0) {
        flag++;
        for (long long i = 0; i < m - 1; i++) cout << ".";
        cout << "#";
      } else {
        flag = 0;
        cout << "#";
        for (long long i = 0; i < m - 1; i++) cout << ".";
      }
    }
    cout << "\n";
  }
}
