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())
mods=n%2

if mods==0:
    print(n//2*n)
else:
    print((n+1)*n//2)
    
for i in range(n):
    if i%2==0:
        print('C.'*(n//2)+'C'*mods)
    
    else:
        print('.C'*(n//2)+'.'*mods)
