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