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==1:
	print(1)
	print("C")
else:
	s=""
	c1=(n+1)//2
	c2=(n)//2
	c=c1*c1+c2*c2
	for i in range(n):
		if i%2==0:
			s+="C"
		else:
			s+="."
	s2="."+s[:-1]
	print(c)
	for i in range(n):
		if i%2==0:
			print(s)
		else:
			print(s2)