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).
import math
n=int(input())

print((math.ceil(n/2)*math.ceil(n/2))+(math.floor(n/2)*math.floor(n/2)))
for i in range(n):
  for j in range(n):
    if (i%2==0 and j%2==0) or (i%2==1 and j%2==1):
      print('C',end='')
     
    else:
      print('.',end='')
  print(end='\n')