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())
cnt = 0
ans = []
for i in range(n):
  s = ['.'] * n
  for j in range(n):
    if j % 2 == i % 2:
      s[j] = 'C'
      cnt += 1
  ans.append(''.join(s))
print(cnt)
for x in ans:
  print(x)