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).
#-------------Program--------------
#----Kuzlyaev-Nikita-Codeforces----
#-------------Training-------------
#----------------------------------

n=int(input())
print((n*n+1)//2)
if n==1:print('C')
else:
    c='C.';e='.C'
    c=c*(n//2)+'C'*int(n%2==1)
    e=e*(n//2)+'.'*int(n%2==1)
    for i in range(n):
        if i%2==0:
            print(c)
        else:
            print(e)