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())
print(((n**2)+1)//2)
for x in range(n):
	a=list("."*n)
	if x%2==0:
		for y in range((n+1)//2):
			a[2*y]="C"
	else:
		for y in range(n//2):
			a[(2*y)+1]="C"
	print("".join(a))
