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())

cnt = 0
for i in range(1,n+1) :
    
    if i%2!=0 :
        if i!=n :
        
            cnt = cnt + 2*i 
            
        else :
            cnt = cnt + i
            
print(cnt)
        
    
for i in range(n) :
    ans = ""
    for j in range(n) :
        
        if i%2==0 :
            if j%2==0 :
            
                ans = ans + "C"
                
            else :
                ans = ans + "."
                
        else :
            
            if j%2==0 :
                ans = ans + "."
                
            else :
                ans= ans + "C"
                
    print(ans)
            
        
            
            