#include<bits/stdc++.h>
using namespace std;
int main()
{
	int n;
	cin>>n;
	int x=n/2+1,y=n/2+1;
	int c=n/2;
	for(int i=1;i<=n;i++)
	{
		for(int j=1;j<=n;j++)
		{
			if(abs(i-x)+abs(j-y)==c) cout<<"#";
			else cout<<".";
		}
		cout<<endl;
	} 
	return 0;
}