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(n*n//2)
    for i in range (n//2):
        print('.C'*(n//2))
        print('C.'*(n//2))

else:
    print(n*(n//2) + n//2 + 1)
    for i in range (n//2 + 1):
        if(i % 2 == 0):
            x = ['C']*(n//2+1)
            print(*x,sep='.')
        else:
            x = ['.']*(n//2+1)
            print(*x,sep='C')