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).
def per(n , x): 
    r =''
    if n % 2 != 0:
        d =( n//2 + 1 )
    else: 
        d = n//2 
    for i in range (d) : 
        r += x 
    if n % 2 != 0:
        return r[:-1]
    return r
n =int(input())
if n % 2 == 0 : 
    print((n//2) * n )
else : 
    print(((n//2)+1)**2 + ((n//2))**2) 
for i in range(n) : 
    if i % 2 == 0 : 
        print(per(n , "C."))
    else:
        print(per(n,".C"))