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))
else:
    halfN = (n // 2)
    print(((halfN + 1) * (halfN + 1)) + (halfN * (halfN)))

for i in range(n):
    result = ''
    isEven = i % 2 == 0
    for j in range(n):
        if(isEven):
            if(j % 2 == 0):
                result += 'C'
            else:
                result += '.'
        else:
            if(j % 2 == 0):
                result += '.'
            else:
                result += 'C'
    print(result)
