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