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=0
q=0
a=[]
b=[]
for x in range(1,n+1):
        a+=['C']
        p+=1
        if p==n:
            break
        a+=['.']
        p+=1
        if p==n:
            break
        #a=
    
        
for y in range(1,n+1):
                b+=['.']
                q+=1
                if q==n:
                    break
                b+=['C']
                q+=1
                if q==n:
                    break
                #b=


                  
    
                
                  
                
                  
                  
                
            
                  
if n%2==0:
    print((n*n)//2)
    p=0
    for x in range(1,n+1):
        print(''.join([str(x) for x in b]))
        p+=1
        #print('')
        if p==n:
            break
        print(''.join([str(x) for x in a]))
        p+=1
        #print('')
        if p==n:
            break
else:
    temp=(n*n)//2
    print(temp+1)
    p=0
    for x in range(1,n+1):
        print(''.join([str(x) for x in a]))
        p+=1
        #print('')
        if p==n:
            break
        print(''.join([str(x) for x in b]))
        p+=1
        #print('')
        if p==n:
            break
