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Provided Code

public class FrogSimulation { private int goalDistance; private int maxHops; private int hopDistance() { } public boolean simulate() { } public double runSimulations(int num) {
    }
}

Part A — 4 Points

Write simulate: return true if frog reached or passed goalDistance. Three stop conditions: goal reached, negative position, or max hops exhausted.

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public boolean simulate()
{
    int position = 0;
    int hops = 0;
    while (position < goalDistance && position >= 0 && hops < maxHops)
    {
        position += hopDistance();
        hops++;
    }
    return position >= goalDistance;
}

Part B — 5 Points

Write runSimulations: run num simulations and return the proportion that returned true as a double.

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public double runSimulations(int num)
{
    int successes = 0;
    for (int i = 0; i < num; i++)
    {
        if (simulate())
        {
            successes++;
        }
    }
    return (double) successes / num;
}

Common Mistakes to Avoid

while (position < goalDistance && hops < maxHops)

while (position < goalDistance && position >= 0 && hops < maxHops)

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