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).
size = int(input())
total = []
if(size != 0):
    if(size % 2 == 0):
        maxCoders = (size * size // 2)
    else:
        maxCoders = (((size * (size + 1)) // 2) - 1)
    for piece in range(0 , size):
        rows = []
        for row in range(0 , size):
            if ((piece + row) % 2) == 0:
                rows.append("C")
            else:
                rows.append(".")
        total.append(rows)
    print(maxCoders)
    for i in total:
        print(*i , sep="")