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).
n = int(input())

if n & 1:
    max_coders = ((n - 1) // 2) * (n - 1) + n
else:
    max_coders = (n // 2) * n

print(max_coders)
for i in range(n):
    if i & 1:
        if n & 1:
            print('.C' * (n - 1), end='')
            print('.', end='')
        else:
            print('.C' * n, end='')
    else:
        if n & 1:
            print('C.' * (n - 1), end='')
            print('C', end='')
        else:
            print('C.' * n, end='')
    print()
