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).
k=0
c=0
s=''
ss=''
n=int(input())
for i in range(n):
    if k%2==0:
        s+='C'
        ss+='.'
    else:
        s+='.'
        ss+='C'
    k+=1
k=0
for i in range(n):
    if k%2==0:
        c+=s.count('C')
    else:
        c+=ss.count('C')
    k+=1
k=0
print(c)
for i in range(n):
    if k%2==0:
        print(s)
    else:
        print(ss)
    k+=1