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())
res=[]
x=n
for i in range(n):
    mat=[]
    for j in range(n//2):
        if i%2==0:
            mat.append('C')
            mat.append('.')
        if i%2!=0:
            mat.append('.')
            mat.append('C')
        if x%2!=0 and i%2==0 and j==(n//2)-1:
            mat.append('C')
        if x%2!=0 and i%2!=0 and j==(n//2)-1:
            mat.append('.')
            
    res.append(mat)
if n%2!=0:
    print(((n*n)//2)+1)
else:
    print(((n*n)//2))
if n==1:
    print('C')
else:
    for line in res:
        print(''.join(line))
