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())
p=n
l=[]
if(n%2==0):
    print(n*(n//2))
else:
    n=n//2
    print((n*(n+1))*2)
for i in range(p):
    if(i%2==0):
        l.append('.')
    elif(i%2!=0):
        l.append('C')
m=''.join(map(str,l))
r = m.replace('C', '%temp%').replace('.', 'C').replace('%temp%', '.') 
for i in range(p):
    if(i%2==0):
        print(m)
    else:
        print(r)
        