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 % 2 == 0:
    print(int((n/2)*n))
    for i in range(int(n/2)):
        print(n*"C.")
        print(n*".C")      
elif n % 2 != 0:
    print((int((n/2)+1))**2 + (int(n/2))**2)
    for i in range(int(n/2)):
        print(n*"C."+"C")
        print(n*".C"+".")
    print(n*"C."+"C")
    
 

    


