#include <bits/stdc++.h>
// #include <atcoder/all>
using namespace std;
using ll = long long;
#define rep(i, n) for (int i = 0; i < (int)(n); i++)

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