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())
arr = [['.' for i in range(n)] for j in range(n)] 
c=0
for i in range(n):
	for j in range(n):
		if i%2==0 and j%2==0 or i%2!=0 and j%2!=0:
			arr[i][j] = 'C'
			c+=1
print(c)
for j in arr:
	print(*j)