public class Test implements Serializable {
	public static void main(String args[]) throws Exception {
		int size = 30;
		int a = 0;
		int b = (1<<size+1)-1;
		
		
		
		
		for (int i=0;i<size;i+=2) {
			print(b, size);
			b ^= (1<<i+2)^(1<<size-i-1);
		
			if (i < size-1) {
				a ^= (1<<i+1)^(1<<size-i);
				print(a, size);
			}

		}
	}
	
	private static void print(int a, int size) {
		for (int i=0;i<size;i++) {
			System.out.print((a&(1<<size-i))==0?" ":"O");
		}
		System.out.println();
	}
	
}