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, trunc

n = int(input())

k1 = 0
line1 = []
b = True
for i in range(n):
    line1.append('C' if b else '.')
    k1 += b
    b = not b
line1 = ''.join(line1)

k2 = 0
line2 = []
b = False
for i in range(n):
    line2.append('C' if b else '.')
    k2 += b
    b = not b
line2 = ''.join(line2)

print(ceil(n / 2) * k1 + trunc(n / 2) * k2)

b = True
for i in range(n):
    print(line1 if b else line2)
    b = not b
