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())
ans=0
for i in range(n,0,-1):
	#print(ans)
	#if i==1 :
		#ans+=1

	if i%2==0:
		ans+=(2*(i//2))-1
	else:
		ans+=(2*((i//2)+1))-1	
print(ans)	


if n%2==0:

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