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())
h = n >> 1

odd = n & 1

if odd:
    hh = h + 1
    t = h * h + hh * hh
    print(t)
    ol = 'C.' * h + 'C' + '\n'
    ev = '.C' * h + '.' + '\n'
    d = ol + ev
    ret = d * h + ol
    print(ret)
else:
    print(h * n)
    ol = 'C.' * h + '\n'
    ev = '.C' * h + '\n'
    d = ol + ev
    ret = d * h
    print(ret)