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())
k = 0
for i in range(n):
    for j in range(n):
        if((i+j)%2==0):
            k+=1
            s[i][j]='C'
        else:
            s[i][j]='.'

print(k)
for i in range(n):
    for j in range(n):
        print(s[i][j])
    print()
