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())
x=m**2
c=0
p=''
if m==1:
	print(1)
	print('C')
else:	
	while x>3:
		c+=1
		p+='C.\n.C'
		x-=4
	if x>1:
		print(c+1)
		print(p+'.C')
	else:
		print(c)
		print(p)