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).
'''HackerRank: Coder'''

if __name__ == '__main__':
    n = int(input())
    arr = [['' for i in range(n)] for j in range(n)]
    count = 0
    for i in range(n):
        for j in range(n):
            if (i % 2 == 0 and j % 2 == 0) or (i % 2 == 1 and j % 2 == 1):
                arr[i][j] += 'C'
                count += 1
            else:
                arr[i][j] += '.'

    print(count)
    for row in arr:
        print(*row)
