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 = input()
if n % 2 == 0 :
    ctr = ( n * n / 2 )
else :
    ctr = ( n / 2 * n / 2 ) + ( ( n / 2 + 1 ) * ( n / 2 + 1 ) )
print (ctr)
i = 0
while i < n :
    mylist = []
    z = 0
    while z < n :
        mylist.append('.')
        z = z + 1
    if i % 2 == 0 :
        j = 0
        while j < n :
            mylist[j] = 'C'
            j = j + 2
    else :
        j = 1
        while j < n :
            mylist[j] = 'C'
            j = j + 2
    for x in xrange(n) :
        print (mylist[x])
    i = i + 1
