using System;

public class BankAccount
{
    public void Open()
    {
        throw new NotImplementedException("You need to implement this function.");
    }

    public void Close()
    {
        throw new NotImplementedException("You need to implement this function.");
    }

    public float Balance
    {
        get
        {
            throw new NotImplementedException("You need to implement this property.");
        }
    }

    public void UpdateBalance(float change)
    {
        throw new NotImplementedException("You need to implement this function.");
    }
}