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())
print(((n**2)//2) if (n**2) % 2 == 0 else (((n//2)+1)**2 + (n//2)**2))
a = []
for i in range(n):
    b = []
    for j in range(n):
        b.append("C" if (i+j) % 2 == 0 else ".")
    a.append(b)
for i in range(n):
    for j in range(n):
        print(a[i][j], end="")
    print()
