import java.util.*;

class Node {
    int row;
    int col;
    Node parent;
    // Node next[];

    Node (int r, int c) {
	row = r; col = c; parent = null;
    }

    Node (int r, int c, Node par) {
	row = r; col = c; parent = par;
    }
}

class Queen {

    static void print_row (int sz, int c) {
	int i;
	for (i = 1; i < c; i++) {
	    System.out.print('.');
	}
	System.out.print('Q');
	for (i = c+1; i <= sz; i++) {
	    System.out.print('.');
	}
	System.out.print('\n');
    }

    static void print_solution (Node t, int sz) {
	while (t != null) {
	    print_row (sz, t.col);
	    t = t.parent;
	}
	return;
    }

    static boolean position_test (Node t, int sz, int c) {
	int diff = 1;
	while (t != null) {
	    if (t.col == c) { return false; }
	    if (t.col - c == diff) { return false; }
	    if (c - t.col == diff) { return false; }
	    t = t.parent;
	    diff = diff + 1;
	}
	return true;
    }

    static void search_bfs (int sz) {
	int i;
	Node cur;
	Node nxt;
	LinkedList<Node> que = new LinkedList();

	for (i = 1; i <= sz; i++) {
	    que.offer(new Node(1, i));
	}

	while ((cur = que.poll()) != null) {
	    if (cur.row == sz) {
		print_solution (cur, sz);
		System.out.print ("\n");
		continue;
	    }
	    for (i = 1; i <= sz; i++) {
		if (position_test (cur, sz, i)) {
		    nxt = new Node (cur.row+1, i, cur);
		    que.offer(nxt);
		}
	    }
	}
    }

    public static void main (String argv[]) {
	search_bfs (8);
	return;
    }
}