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).
hat = int(input())
total = 0
lst = []
for i in range(0, hat):
    if i % 2 == 0:
        x = ""
        for j in range(hat):
            if j % 2 == 0:
                x += "C"
                total += 1
            else:
                x += "."
        lst.append(x)
    else:
        y = ""
        for j in range(hat):
            if j % 2 == 0:
                y += "."
                total += 1
            else:
                y += "C"
        lst.append(y)

print(total)
print("\n".join(lst))
