Advent of Code - 2019 - Day 1 - JavaScript

solution.js

// part 1
const fuel = x => Math.floor(x/3) - 2;
$0.textContent.split("\n").map(Number).map(fuel).filter(i => i > 0).reduce((a, b) => a + b, 0)

// part 2
($0.textContent.split("\n").map(Number).filter(i => i > 0).map(mass => {const res = []; let i = mass; while (i > 0) {i = fuel(i); res.push(i)} return res})).flat().reduce((a, b) => a + b, 0)