Hacker Rank Problem

poisonPlants.js

const data = [6, 5, 8, 4, 7, 10, 9];

const daysTillPlantDeath = (toxicities, daysElapsed) => {
  const livingPlants = toxicities.filter((poisonLevel, idx) => (
    idx === 0 || (idx > 0 && poisonLevel <= toxicities[idx - 1])
  ));
  return livingPlants.join('') === toxicities.join('') ?
    daysElapsed : daysTillPlantDeath(livingPlants, daysElapsed + 1);
};

daysTillPlantDeath(data, 0);