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())
pair = n//2
num_C = pair*2
odd = "C."*pair
eve = ".C"*pair

if n%2 !=0:
    odd += "C"
    eve += "."
    num_C += 1
    num_C *= n//2
    num_C += pair+1
else:
    num_C *= n//2
    

print (num_C)

for x in range(1,n+1):
    if x%2 != 0:
        print (odd)
    else:
        print (eve)
        









    
        
                      

                
        

    
 





        




    




    

    
    

        
        
        
    
    

    
        



        
        
        
           
        
        
    
    




    
            
        





            
        
            

        
            



        
        
    
        



            


    
    







    



        
        
        
        


            



        
            

    


    

    



        


        



    
        
        

    







    
    
 

    

        
    
            
    




    


        



    





        
            
        
    
