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).
# https://codeforces.com/contest/384/problem/A
import math

n = int(input())
print((math.ceil(n / 2) ** 2) + (n // 2) ** 2)
even = ""
odd = ""

for j in range(n):
    if j % 2 == 0:
        even += "C"
        odd += "."
    else:
        even += "."
        odd += "C"

for i in range(n):
    if i % 2 == 0:
        print(even)
    else:
        print(odd)
