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=int(input())
#n,m=map(int,input().split())

#a=list(map(int,input().split()))

#b=list(map(int,input().split()))


n=int(input())

x=(n+1)//2

print(x*x+(n-x)*(n-x))

for i in range(n):
    for j in range(n):
        print('C' if j%2==i%2 else '.',end='')
    print()
