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())
ans= (((n+1)//2)**2)+((n//2)**2)
#for i in range(n):
#    for j in range(n):
#        if i%2==0:
print(ans,end='\n')
for i in range(n):
    for j in range(n):
        if ((i%2==0 and j%2==0)or(i%2==1 and j%2==1)):
           print('C',end='') 
        else:
           print('.',end='')   
    print(end='\n')