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())
count=0
if n%2==0:
    print(int((n/2)*n))
    for x in range(n):
        for x in range(int(n/2)):
            if count%2==0: print("C.", end="")
            if count%2!=0: print(".C", end="")
            print()
        count+=1
else:
    x = int(n/2 + 1)
    print(x*x + (x-1)*(x-1))
    for x in range(n):
        for x in range(int(n/2)):
            if count%2==0:
                print("C.", end="")
                print("C", end="")
            if count%2!=0:
                print(".C", end="")
                print(".", end="")
            print()
        count+=1

