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())
count = 0
board = [['' for i in range(n)] for j in range(n)]
if n == 1:
    print("1\n" + 'C')
else:
    even = True
    for row in range(n):
        for col in range(n):
            if even:
                if col % 2 == 0:
                    board[row][col] = 'C'
                    count += 1
                else:
                    board[row][col] = '.'

            else:
                if col % 2 == 1:
                    board[row][col] = 'C'
                    count += 1
                else:
                    board[row][col] = '.'
        even = not even
    print(count)
    for row in range(n):
        for col in range(n):
            print(board[row][col], end='')
        print()
