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 sys
from math import ceil

def main():
    n = int(sys.stdin.read().strip())
    t = int(ceil(n/2))
    return t*n - n%t, '\n'.join(''.join('.C'[not (i+j)%2] for j in range(n)) for i in range(n))
        
print(*main(), sep='\n')
