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())
lst = []

def newlst(l):
    newl = []
    for ch in l:
        if ch == '.':
            newl.append('C')
        else:
            newl.append('.')
    return newl

for i in range(1,n+1):
    if i%2 == 0:
        lst.append('.')
    else:
        lst.append("C")

print(int(n*n/2))
print(''.join(map(str, lst)))

for i in range(n-1):
    lst = newlst(lst)
    print(''.join(map(str, lst)))
