Iahub likes chess very much. He even invented a new chess piece named Coder. A Coder can move (and attack) one square horizontally or vertically. More precisely, if the Coder is located at position (*x*, *y*), he can move to (or attack) positions (*x* + 1, *y*), (*x*–1, *y*), (*x*, *y* + 1) and (*x*, *y*–1).

Iahub wants to know how many Coders can be placed on an *n* × *n* chessboard, so that no Coder attacks any other Coder.
The first line contains an integer *n* (1 ≤ *n* ≤ 1000).
def test(n):
	rowOne = n//2
	rowTwo = (n - 1)//2
	
	lineOne = ""
	lineTwo = str()
	for i in range(n):
		if i % 2 == 0:
			lineOne += ("C")
			lineTwo += (".")
		else:
			lineOne += (".")
			lineTwo += ("C")
	
	print(rowOne**2 + rowTwo ** 2)
	for i in range(n):
		if i % 2 == 0:
			print(lineOne)
		else:
			print(lineTwo)
			
			
test(int(input()))
		
	
	
