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())
count = 0
for i in range(1, n + 1):
    for j in range(1, n + 1):
        if ((i % 2 == 0 and j % 2 == 0) or (i % 2 == 1 and j % 2 == 1)):
            count += 1
print(count)
for i in range(1, n + 1):
    for j in range(1, n + 1):
        if ((i % 2 == 0 and j % 2 == 0) or (i % 2 == 1 and j % 2 == 1)):
            print('C')
        else:
            print('.')