extern int putchar(int c);

int up[15], down[15], rows[8], x[8];
void queens(int c), print();

int main()
{
	int i;
	for (i = 0; i < 15; i++)
		up[i] = down[i] = 1;
	for (i = 0; i < 8; i++)
		rows[i] = 1;
	queens(0);
	return 0;
}

void queens(c)                                                  
{
	int r;

	for (r = 0; r < 8; r++)
		if (rows[r] && up[r-c+7] && down[r+c]) {
			rows[r] = up[r-c+7] = down[r+c] = 0;
			x[c] = r;
			if (c == 7)
				print();
			else
				queens(c + 1);
			rows[r] = up[r-c+7] = down[r+c] = 1;
		}
}

void print()
{
	int k;

	for (k = 0; k < 8; k++) {
		putchar(x[k] + '1');
		putchar(' ');
	}
	putchar('\n');
}