SJSU/Udacity CS046

The answer in the video is wrong. See if you can spot the error.

The problem is that there are two i++: in the for loop and in the else.

It is always dangerous to change the variable that is controlled by the for loop. A while loop is the safer choice:

            int i = 0;
            while (i < cars.size())
            {
                Car c = cars.get(i);
                c.drive();
                if (c.hasArrived())
                {
                    cars.remove(i);
                }
                else
                {
                    i++;
                }
            }

Alternatively, if you use a for loop and remove elements, traverse the list backwards:

            for (int i = cars.size() - 1; i >= 0; i--)
            {
                Car c = cars.get(i);
                c.drive();
                if (c.hasArrived())
                {
                    cars.remove(i);
                }
            }