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).
number = int(input())
start  = 1
counter = 0
arr     = []
for i in range( 0 , number) :
    start = 0 if start == 1 else 1
    now   = "C" if start == 0 else "."
    ar    = ""
    for j in range(0 , number) :
        ar += "C"if now == "C" else  "."
        now = "." if now == "C" else  "C"
        counter += 1 if now == '.' else 0
    arr.append(ar)
print(counter)
for i in arr :
    print(i)