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