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())
x="C."
y='.C'
c=n//2
ans=2*c*c
if n%2==0:
	print(ans)
else:
	ans+=n
	print(ans)
for i in range(0,n):
	for j in range(0,n):
		if i%2==0:
			print(x[j%2],end='')
		else:
			print(y[j%2],end='')
	print()