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("C."*(int(n//2)));print(".C"*(int(n//2)))
else:
    print((int(n // 2) + 1) ** 2 + (int(n // 2)) ** 2)
    for i in range(int(n//2)):
        print("C." * (int(n // 2)) + "C");print(".C" * (int(n//2)) + ".")
    print("C." * (int(n // 2)) + "C")