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())
arr=""
brr=""
for x in range(n):
    if(x%2):
        arr+='C'
        brr+='.'
    else:
        arr+='.'
        brr+='C'
print((n*n+1)//2)
for x in range(n):
    if(x%2):
        print(arr)
    else:
        print(brr)