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).
import math as ma
x=int(input())
print(ma.ceil(x/2)**2+ma.floor(x/2)**2)
s1=''
s2=''
for n in range(x):
	if n%2==0:
		s1+='C'
		s2+='.'
	else:
		s1+='.'
		s2+='C'
for n in range(x):
	if n%2==0:
		print(s1)
	else:
		print(s2)