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())
count = n//2 * n
print(count)
for i in range(n):
 	if n % 2 == 0:
 		if i % 2 == 0:
 			print('C.' * int(n/2))
 		else:
 			print('.C' * int(n/2))
 	else:
 		if i % 2 == 0:
 			print('C.' * int(n//2) + 'C')
 		else:
 			print('.C' * int(n//2) + '.') 		
			
