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).
import math
n=int(input())

if ((n & 1) == 0):
    total_coder=int(n*n/2)
    print(total_coder)
else:
    total_coder=int(math.ceil(n*n/2))
    print(total_coder)
    
for i in range(n): 
    if ((i & 1) == 0):
        for_even_place="C."
        z= math.ceil(n/2)
        final_string=for_even_place*z
        print(final_string[0:n])
    else:
        for_odd_place=".C"
        z= math.ceil(n/2)
        final_string=for_odd_place*z
        print(final_string[0:n])    