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())
chessboard = []
count = 0
for i in range(n):
  temp = ["."] * n
  if i % 2 == 0:
    for j in range(0, n, 2):
      count += 1
      temp[j] = "C"
  else:
    for k in range(1, n, 2):
      count += 1
      temp[k] = "C"
  chessboard.append(temp)
print(count)
for i in range(n):
  print("".join(chessboard[i]))