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())
s1=""
for i in range(1,n+1):
    if i%2:
        s1+="C"
    else:
        s1+="."
s2=s1.replace("C.", ".C")
s2=s2.replace("CC", "C.")
if n%2:
    print(int((n/2+1)**2 + (n/2)**2))
else:
    print(int(n**2/2))
for i in range(1,n+1):
    if i%2:
        print(s1)
    else:
        print(s2)