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())
c=0
for i in range(1,n+1):
	if i%2==1:
		for j in range(1,n+1):
			if j%2==1:
				if j==n:
					c+=1
				else:
					c+=1
	else:
		for j in range(1,n+1):
			if j%2==0:
				if j==n:
					c=c+1
				else:
					c=c+1
print(c)
for i in range(1,n+1):
	if i%2==1:
		for j in range(1,n+1):
			if j%2==1:
				if j==n:
					print("c")
					c+=1
				else:
					print("c",end="")
					c+=1
			else:
				if j==n:
					print(".")
				else:
					print(".",end='')
	else:
		for j in range(1,n+1):
			if j%2==1:
				if j==n:
					print(".")
				else:
					print(".",end='')
			else:
				if j==n:
					print("c")
					c=c+1
				else:
					print("c",end='')
					c=c+1
	