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 CreateBoard(n):
    mat = []
    for i in range(n):
        if i % 2 == 0:
            if n % 2 == 0:
                mat.append('C.'*(n//2))
            else:
                mat.append('C.'*(n//2+1))
        else:
            if n % 2 == 0:
                mat.append('.C'*(n//2))
            else:
                mat.append('.C'*(n//2+1))
    return mat
                

n = int(input())

if n % 2 == 0:
    print(n * n//2)
    for row in CreateBoard(n):
        print(row)
else:
    print((n//2 + 1)**2 + (n//2)**2)
    for row in CreateBoard(n):
        print(row)