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 collections import *
import sys  
input=sys.stdin.readline

# "". join(strings)  
    
def ri():
    return int(input())
 
def rl():
    return list(map(int, input().split()))
    
n = ri()

if n % 2 == 0:
	print(n // 2 * n)
	for i in range(n):
		if i % 2 == 0:
			print("C."*(n//2))
		else:
			print(".C"*(n//2))

if n % 2 == 1:
	k = n // 2 # n = 2*k + 1
	print((k+1)**2 + k**2)
	for i in range(n):
		if i % 2 == 0:
			print("C."*k + "C")
		else:
			print(".C"*k + ".")
