day7-part2.js

inputString.split('\n').flatMap((e, i) => i === 0 ? [e, e, e] : e).map((e, i) => i === 0 ? window.dirSizes = {} : i === 1 ? window.dirStack = [] : e.substring(0, 4) === '$ cd' ? e.substring(5) === '..' ? (window.dirSizes[window.dirStack.slice(0, -1).reduce((a, b) => a + '/' + b, '')] += window.dirSizes[window.dirStack.reduce((a, b) => a + '/' + b, '')]) | window.dirStack.pop() : window.dirStack.push(e.substring(5)) : e.substring(0, 4) === '$ ls' ? window.dirSizes[window.dirStack.reduce((a, b) => a + '/' + b, '')] = 0 : e.split(' ')[0] === 'dir' ? '' : window.dirSizes[window.dirStack.reduce((a, b) => a + '/' + b, '')] += parseInt(e.split(' ')[0])).map((e, i) => i === 0 ? Array(window.dirStack.length).fill(0) : Object.keys(window.dirSizes)).slice(0, 3).map((e, i) => i === 0 ? e.forEach(_ => (window.dirSizes[window.dirStack.slice(0, -1).reduce((a, b) => a + '/' + b, '')] += window.dirSizes[window.dirStack.reduce((a, b) => a + '/' + b, '')]) | window.dirStack.pop()) : e).slice(1).map(a => a.map(b => window.dirSizes[b]).sort((a, b) => a-b)).map((e, i) => i === 0 ? window.neededSpace = 30000000 - 70000000 + e[e.length-1] : e)[1].find(a => a > window.neededSpace)