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).

n=int(input())
if(n%2==0):
	a=n//2
	print(n**2//2)
	for i in range(1,n+1):
		if(i%2!=0):
			print("C."*a)
		else:
			print(".C"*a)
	
else:
	a=n//2
	print((a+1)*(a+1)+a*a)
	for i in range(1,n+1):
		if(i%2!=0):
			print("C."*a+"C")
		else:
			print(".C"*a+".")

