#include <bits/stdc++.h>
using namespace std;
#include <atcoder/all>
using namespace atcoder;
#define rep(i, s, e) for (int i = s; i < e; ++i)
#define sort_(a) stable_sort(a.begin(), a.end())
#define rsort(a) stable_sort(a.rbegin(), a.rend())
#define sum(a) accumulate(a.begin(), a.end(), 0LL)
#define join(a, d) accumulate(a.begin() + 1, a.end(), a[0], [](string s, string t) { return s + d + t; })
#define all(a) a.begin(), a.end()
#define degrees(a) a * 180.0 / M_PI;
#define radians(a) (a * M_PI) / 180.0;
typedef long long ll;
const long MOD = 1e9 + 7;

int main(int, [[maybe_unused]] char *argv[]) {
#ifdef DEBUG
  freopen(argv[1], "r", stdin);
#endif

  ios_base::sync_with_stdio(false);
  cin.tie(0);
  cout << fixed << setprecision(15);

  int H, W;
  cin >> H >> W;

  vector<vector<char>> ans(H, vector<char>(W, 'O'));
  rep(i, 0, H) {
    if (i % 2 == 0) {
      for (int j = 0; j < W; j += 4) {
        ans[i][j] = 'X';
        if (j + 1 < W) ans[i][j + 1] = 'X';
      }
    } else {
      for (int j = 2; j < W; j += 4) {
        ans[i][j] = 'X';
        if (j + 1 < W) ans[i][j + 1] = 'X';
      }
    }
  }
  rep(i, 0, H) {
    rep(j, 0, W) {
      cout << ans[i][j];
    }
    cout << "\n";
  }
  return 0;
}