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())
if n % 2 == 0:
  print((n // 2) * n)
else:
  a = -(-n) // 2
  b = n - a
  print(a * a + b * b)
for i in range(n):
    ans = ''
    for j in range(n):
      if (i + j) % 2 == 0:
        ans += 'C'
      else:
        ans += '.'
    print(ans)
  	       	 		 	 		  	   	 			