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())
row=[]
chess=[]
if n%2==0:
    maximum_number_of_Coders=2**(n-1)
else:
    maximum_number_of_Coders=(n**2)//2+n//2
for c in range(0,n):
        row=[]
        for r in range(0,n):
            if (c+r)%2==0:
                row.append("C")
            else:
                row.append(".")
        chess.append(row)
print(maximum_number_of_Coders)
for i in chess:
    print("".join(i))

