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