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())
if n % 2 == 0:
    print(n**2 // 2)
else:
    print(n**2 // 2 + 1)

odd = False
for i in range(1,n+1):
    str = ""
    while len(str) != n:
        if (odd):
            str += "."
        if(not odd):
            str +="C"
        odd = not odd
    if len(str) % 2 == 0:
        odd = not odd 
    print(str)