// visit https://adventofcode.com/2019/day/1/input

const masses = document.querySelector('pre').innerText.split(/\r?\n/);

function calculateFuel(mass) {
  return Math.floor(mass / 3) - 2 > 0 ? Math.floor(mass / 3) - 2 : 0;
}

function calculateTotalFuel(masses) {
  return masses.map(mass => calculateFuel(mass)).reduce((total, fuel) => total + fuel)
}

calculateTotalFuel(masses);