Solution for the Frog Simulation free response on the 2018 AP computer science exam - https://compsci.rocks

runSimulation.java

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

simulate.java

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