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).
s1, s2 = "", ""
n = int(input())

if n%2==0:
    print(int((n/2)*n))
    for y in range(int(n/2)):
        s1+="C."
        s2+=".C"
    for x in range(int(n/2)):
        print(s1)
        print(s2)

if n%2!=0:
    x = int(n/2 + 1)
    print(x*x + (x-1)*(x-1))
    for y in range(int(n / 2)):
        s1+="C."
        s2+=".C"
    for z in range(int(n/2)):
        print(s1+"C")
        print(s2+".")
    print(s1+"C")