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).
x = int(input())
if x % 2 == 1:
    y = x*x//2+1
else:
    y = x*x
print(y)
j = ''
k = ''
for i in range(1, x+1):
    if i%2 == 1:
        j += 'C'
    else:
        j += '.'
for i in range(1, x+1):
    if i%2 == 1:
        k += '.'
    else:
        k += 'C'
for i in range(1, x+1):
    if i%2 == 1:
        print(j)
    else:
        print(k)
