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())
if n==1:
    print("1")
    print("C")
else:
    if n%2==0:
        print(n*(n//2))
        for i in range(1,n+1):
            if i%2!=0:
                print("C."*(n//2))
         
            else:
                print(".C"*(n//2))
                
                
    else:
        print((n//2+1)**2 + (n//2)**2)
        for i in range(1,n+1):
            if i%2!=0:
                print("C."*(n//2)+"C")
                
            else:
                print(".C"*(n//2)+".")
