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())
CodeR = 0
if N%2 == 0:
    CodeR = N* N//2
elif(N%2 != 0):
    CodeR = (N* (N//2)) + (N//2) + 1
print(CodeR)
for i in range(N):
    if(i%2 == 0):
        if (N%2 == 0):
            print("C."*(N//2))
        elif(N%2 != 0):
            print("C."*(N//2)+"C")
    else:
        if (N%2 == 0):
            print(".C"*(N//2))
        elif(N%2 != 0):
            print(".C"*(N//2)+".")