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).
def main():
    n = int(input())
    board = [["."] * n for _ in range(n)]
    
    for i in range(0, n, 1):
        for j in range(i % 2, n, 2):
            board[i][j] = "C"

    print("\n".join([" ".join(row) for row in board]))

if __name__ == "__main__":
    main()
