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).
m = int(input())
s = ""
for i in range(1,m+1):
	if i%2!=0:
		for j in range(1,m+1):
			if j%2!=0:
				s += "C"
			elif j%2==0:
				s += "."				
	elif i%2==0:
		for j in range(1,m+1):
			if j%2!=0:
				s += "."
			elif j%2==0:
				s += "C"
print(s.count("C"))				
for k in range(0,len(s),m):
	print(s[k:k+m])		