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).
from math import ceil
t=int(input())
print(ceil((t**2)/2))
p=t
i='C'
while p>0:
	for k in range(t):
		if k==t-1:
			print(i)
			if t%2!=0:
				if i=='C':
					i='.'
				else:
					i='C'
		else:
			print(i,end='')
			if i=='C':
				i='.'
			else:
				i='C'
	p-=1