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*n)
else:
    print((n//2+1)*n - (n//2))



aux = 0
for i in range(n):
    a = ["."]*n
    for j in range(aux, n, 2):
        a[j] = "C"
    if aux == 0:
        aux = 1
    elif aux == 1:
        aux = 0
    print("".join(map(str, a)))
        