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).
from math import ceil,floor
n = int(input())

count = 0
odd = 0
even = 0 
if n%2 != 0:
    odd = n
    even = n-1
else:
    odd = n-1
    even = n


if n%2 != 0:
    count = ceil(((even-2)/2)+1)*floor(n/2) +ceil((((odd-1)-1)/2)+1)*ceil(n/2)
else:
    count = ceil(((even-2)/2)+1)*ceil(n/2) +ceil((((odd-1)-1)/2)+1)*ceil(n/2)

print(count)

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