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).
def evenGrid(n):
    result = list()
    cur1 = ""
    cur2 = ""
    for i in range(0,n,2):
        cur1+="C."
    for i in range(0,n,2):
        cur2+=".C"
    for i in range(0,n,2):
        result.append(cur1)
        result.append(cur2)

    return result

# build the grid when n is odd
def oddGrid(n):
    result = list()
    cur1 = ""
    cur2 = ""
    for i in range(0,n,2):
        cur1+="C."
    cur1 = cur1[:-1]
    for i in range(0,n,2):
        cur2+=".C"
    cur2 = cur2[:-1]
    for i in range(0,n,2):
        result.append(cur1)
        result.append(cur2)
    del result[-1]
    return result


# calculate the total pieces based on n being odd or not
def solve(n):
    result = ()
    if(n%2==0):
        result = evenGrid(n)
        print(int((n/2) * n))
    else:
        result = oddGrid(n)
        print(((n/2)+1)*((n/2)+1) + (n/2)*(n/2))

    for i in range(0,len(result)):
        print(result[i])


n = int(input())
solve(n)