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).
a=int(input())
even=None
odd=None
if a%2==0:
  even=a//2
  odd=a-even
else:
  odd=a//2
  even=a-odd
i=even*even+odd*odd
print(i)
for num in range(1,a+1):
  for nums in range(1,a+1):
    if num%2==0:
      if nums%2==0:
         print('C',end='')
      else:
        print('.',end='')
    if num%2!=0:
      if nums%2!=0:
        print('C',end='')
      else:
        print('.',end='')   
  print()