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 time
number=int(input())
#start_time=time.time()
tota_no_of_coders=((number+1)//2)*((number+1)//2)
tota_no_of_coders=tota_no_of_coders+(number//2)*(number//2)
print(tota_no_of_coders)
def make_line(number,flag):
    dict={}
    dict[0]='C'
    dict[1]='.'
    line=''
    for i in range(number):
        line=''.join([line,dict[flag]])
        flag=(flag+1)%2
    return line
line1=make_line(number,0)
line2=make_line(number,1)


def print_lines(number,line_number):
    if(line_number%2==0):
        eval('print(line1)')
    else:
        eval('print(line2)')


'''
def print_line(number,line_number):
    dict={}
    dict[0]='C'
    dict[1]='.'
    flag=line_number%2
    for i in range(number):
        print(dict[flag],end='')
        flag=(flag+1)%2
    print('')
'''
for i in range(number):
    print_lines(number,i)
#end_time=time.time()
#print(end_time-start_time)