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 ve_bang(n):
    if(n%2):
        print(int(n*n/2)+1)
        for i in range(n):
            if(i%2):
                print(".C"*round((n-1)/2)+'.')
            else:
                print("C."*round((n-1)/2)+'C')
    else:
        print(round(n*n/2))
        for i in range(n):
            if(i%2):
                print("C."*round(n/2))
            else:
                print(".C"*round(n/2))
    pass
n=int(input())
ve_bang(n)