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())
s = 'C.' * 500
p = '.C' * 500

if n%2 == 0:
    print(n*(n//2))
else:
    print((n-1)*(n-1)//2 + n)
    
for i in range(n):
    if i%2 == 0:
        print(s[:n:])
    else:
        print(p[:n:])