Feeder free response answer 2024

Feeder is #1 from the from the 2024 AP Computer Science A Free Response problems.

https://apcentral.collegeboard.org/media/pdf/ap24-frq-comp-sci-a.pdf

Part (a) `simulateOneDay` method

public void simulateOneDay(int numBirds)
{
    if(Math.random() < 0.95)
    {
        int foodPerBird = (int) (Math.random() * 41) + 10;
        currentFood -= numBirds * foodPerBird;
        if(currentFood < 0)
            currentFood = 0;
    }
    else
    {
        currentFood = 0;
    }
}

For more on working with Math.random() see Generating numbers with Math.random().

Part (b) `simulateManyDays` method

public int simulateManyDays(int numBirds, int numDays)
{
    int daysLeft = numDays, foundFood = 0;
    while(daysLeft > 0 && currentFood > 0)
    {
        daysLeft--;
        foundFood++;
        simulateOneDay(numBirds);
    }
    return foundFood;
}

2024 AP CS Exam Free Response Solutions

Help & comments

Get help from AP CS Tutor Brandon Horn

See an error? Question? Please comment below.

Comment on Feeder

2024-05-13 comment

(Email withheld)

If I made the random number 0 - 100 do you think I would get points off? I adjusted the if statement accordingly to: if (randomNum < 95)

Response

Although it is not necessary to convert the number returned by Math.random into an int, a solution that did so correctly would not be penalized.