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())
cnt = 0
board = ''
for i in range(n):
    for j in range(n):
        if i % 2:
            if j % 2: 
                board += 'C'
                cnt += 1
            else: board += '.'
        else:
            if j % 2: board += '.'
            else: 
                board += 'C'
                cnt += 1
    board += '\n'
print(cnt)
print(board[:len(board) - 1])
	 	  	 	 		 						  	  	 		 	