// Public methods
public void operate(int index, int value)
{
if (!timer.count_down_start)
{
timer.count_down_start = true; Debug.Log("started"); refresh.set_clickable(false);
}
if (sum.the_sum <= target.target_number)
{
sum.the_sum += value;
sum.refresh_sum();
}
else
{
sum.the_sum -= value;
sum.refresh_sum();
}
}
