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
t=int(input())
n=0
for i in range(t):
    for j in range(t):
        if(i%2==j%2):
            n=n+1
print(n)
for i in range(t):
    for j in range(t):
        if(i%2==j%2):
            sys.stdout.write("C") 
        else:
            sys.stdout.write(".") 
    sys.stdout.write("\n")