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).
a=int(input())

if a%2==0:
    nc=(a//2)*a
else:
    nc=(a//2)**2+(a//2+1)**2

s=""
print(nc)
for i in range(a):
    if i%2==0:
        for j in range(a):
            if j%2==0:
                s=s+"C"
            else:
                s=s+"."
    else:
        for j in range(a):
            if j%2==0:
                s=s+"."
            else:
                s=s+"C"
    
    print(s)
    s=""