#include <bits/stdc++.h>
using namespace std;

int main()
{
    int limit;
    cin >> limit;

    for (int i = 1; i <= limit; i++) {
        for (int j = 1; j <= limit - i; j++) {
            cout << "  ";
        }

        for (int j = 1; j <= i; j++) {
            cout << "O";
        }

        cout << "\n";
    }
}