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())
f = [1]*(n+1)
j = 1
while j < n:
    j += 1
    f[j] = f[j-1] + f[j-2]
print(f[n])

l = [[],[]]
for i in range(n):
    l[0].append("C" if i%2 == 0 else ".")
    l[1].append("C" if i%2 == 1 else ".")
for i in range(n):
    print(*l[i%2], sep='')
