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:
    A=(n//2)*(n//2)
    B=A+A;
    print(B)
else:
    A=(n//2)+1
    B=A*A
    C=(n//2)
    D=C*C;
    print(B+D)
if(1):
    for i in range(0,n):
        for j in range(0,n):
            if i%2==0:
                if j%2==0:
                    print("C",end='')
                else:
                    print(".",end='')
            else:
                if j%2==0:
                    print(".",end='')
                else:
                    print("C",end='')
        print()