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())
c=0
if n%2!=0:
	e=(n-1)//2
	o=n-e
	c+=((n-1)//2)*e
	c+=((n+1)//2)*o
else:
	e=n//2
	o=n-e
	c+=(n//2)*(e+o)
print(c)
for i in range(1,n+1):
	for j in range(1,n+1):
		if i%2!=0 and j%2!=0:
			print("C",end="")
		elif i%2!=0 and j%2==0:
			print(".",end="")
		elif i%2==0 and j%2!=0:
			print(".",end="")
		elif i%2==0 and j%2==0:
			print("C",end="")
	print() 

