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())
p=a//2
ans=a*a
if a%2==0:
  ans=ans//2
else:
  ans=(ans+1)//2
print(ans)
for num in range(1,a+1):
  if a%2==0:
    if num%2==0:
      print('.C'*p)
    else:
      print('C.'*p)
  else:
    if num%2==0:
      print('.C'*p+'.')
    else:
      print('C.'*p+'C')
  