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())
d = []
for k in range(n):
    if k % 2 == 0:
        w = 'C'
    else:
        w = '.'
    while True:
        if len(w) == n:
            break
        else:
            if w[-1] == '.':
                w += 'C'
            else:
                w += '.'
    d.append(w)
print(int(((n*n+1)/2)//1))
for k in d:
    print(k)