#include <stdio.h>
#define N 8
int queens[N];
void printBoard() {
for (int i = 0; i < N; i++) {
for (int j = 0; j < N; j++) {
if (queens[i] == j) {
printf("Q ");
} else {
printf(". ");
}
}
printf("\n");
}
printf("\n");
}
int isSafe(int row, int col) {
for (int i = 0; i < row; i++) {
if (queens[i] == col || queens[i] - col == i - row || queens[i] - col == row - i) {
return 0;
}
}
return 1;
}
void solve(int row) {
if (row == N) {
printBoard();
return;
}
for (int col = 0; col < N; col++) {
if (isSafe(row, col)) {
queens[row] = col;
solve(row + 1);
}
}
}
int main() {
solve(0);
return 0;
}