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).
s=int(input())
cnt=0
c=[]
for i in range(s):
  x=[]
  for j in range(s):
    if i%2==0:
      if j%2==0:
        x.append('C')
      else:
        x.append('.')
    else:
      if j%2==0:
        x.append('.')
      else:
        x.append('C') 
  c.append(x)
print(c.count('C'))  
print('\n'.join(map(''.join, c)))
