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).
class COUT:
    def __lshift__(self, other):
        print(other, end='')
        return self
class using:
    @staticmethod
    def namespace(arg):
        return
endl = "\n"
cout = COUT()
std = "std"

#include <iostream>
using.namespace(std);

def solve(n):

    if(n%2==0):
        ans=int((n/2))*n    # type fix 
    else:
        ans=int(((n+1)/2)*((n+1)/2))
        
        ans+=int((n/2))*int((n/2))
        
    print(ans)
    for i in range(1,n+1):
        for j in range(1,n+1):
            if(i%2==1 and j%2==1):
                if j!=n:
                    cout<<"C";
                else:
                     cout<<"C\n";
            elif(i%2==1 and j%2==0):
                if(j!=n):
                    cout<<".";
                else:
                    cout<<"."<<endl;
            elif(i%2==0 and j%2==0):    
                if(j!=n):
                    cout<<"C";
                else:
                    cout<<"C"<<endl;
 
            elif(i%2==0 and j%2==1):
                if(j!=n):
                    cout<<".";
                else:
                    cout<<"."<<endl;
          
 

n = int(input())
solve(n)