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())
l = []
n1 = 0
l1 = ['.' ] * n
l2 = ['.' ] * n
n2 = 0
n3 = 0
for i in range(n):
	if i % 2 == 0:
		l1[i] = 'C'
		n1 += 1

for i in range(n):
	if i % 2 != 0:
		l2[i] = 'C'
		n2 += 1


for i in range(n):
	if i % 2 == 0:
		l.append(l1)
		n3 += n1
	else:
		l.append(l2)
		n3 += n2
print(n3)
for i in l:
	print(*i, sep = '')
