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=[]
c=0
for i in range(1,n+1):
	for j in range(1,n+1):
		if i%2==1:
			if j%2==1:
				l.append("C")
				c+=1
			else:
				l.append(".")
		else:
			if j%2==1:
				l.append(".")
			else:
				l.append("C")
				c+=1
print(c)
s="".join(l)
for i in range(0,len(l),n):
	t=slice(0+i,n+i)
	print(s[t])
