At first I thought "Collab with Cory would be nice" - and then he did not just reference the works of @doctorow.pluralistic.net , but @nealstephenson.bsky.social as well? Make it happen, please!
www.youtube.com/watch?v=vS6H...
youtube.com
The PROBLEM with Capitalism - Smarter Every Day 316
YouTube video by SmarterEveryDay
![// My solution for day 12 to this challenge: https://www.reddit.com/r/adventofcode/comments/1p2ral9/flowless_challenge_2025/
// Purely functional and branchless programming
// Just paste this code into the developer console on https://adventofcode.com/2025/day/12/input (try F12 or CTRL+I in your browser)
// The number is the solution to the first part of the challenge.
// There is no second part to this days challenge, just have 23 stars total
const parseInput = input => input
.trim()
.split('\n\n')
.reduce(([boxes, regions], block) => {
const lines = block.split('\n')
const hasX = +(lines[0].search('x') != -1)
boxes = [[...boxes, lines.slice(1).join('').split('').filter(c => c == '#').length], boxes][hasX]
regions = [regions, lines.reduce((reg, line) => [...reg, line.match(/\d+/g)?.map(Number)], regions)][hasX]
return [boxes, regions]
}, [[], []])
const part1 = input => {
const [boxes, regions] = parseInput(input)
return regions.reduce((total, region) => {
const area = region[0] * region[1]
const needed = region.slice(2).reduce((acc, cur, i) => acc + cur * boxes[i], 0)
return total + +(area >= needed)
}, 0)
}
console.time('Advent of Code Day 12 both parts flowless')
console.log(part1(document.body.innerText.trim()))
console.timeEnd('Advent of Code Day 12 both parts flowless')](https://cdn.bsky.app/img/feed_thumbnail/plain/did:plc:imdouboftoohbcdk4tvnlez7/bafkreieu72jxdxemwbzkckxtqu57ie4bh4dt4czsattngwocjfkzg5gcmy)
![// My solution for day 7 to this challenge: https://www.reddit.com/r/adventofcode/comments/1p2ral9/flowless_challenge_2025/
// Purely functional and branchless programming
// Just paste this code into the developer console on https://adventofcode.com/2025/day/7/input (try F12 or CTRL+I in your browser)
// The two numbers are the results for the first and second part for your personal input
const steps = count => [...(new Array(count)).keys()]
const memo = new Map()
const solve = (grid, timelines, row, col) => {
const key = `${row},${col}`
const val = memo.get(key)
|| (row == grid.length - 1) * (timelines + 1)
|| (grid[row][col] == '.') * solve(grid, timelines, row + 1, col)
|| solve(grid, timelines, row + 1, col - 1) + solve(grid, timelines, row + 1, col + 1)
memo.set(key, val)
return val
}
const part1 = input => steps(input.length)
.slice(1)
.reduce((total, row) => steps(input[row].length)
.reduce((t, col) => {
const above = +('S|'.includes(input[row - 1][col]))
const splitter = +(input[row][col] == '^')
input[row][col] = [input[row][col], '|'][above * !splitter]
input[row][col - 1] = [input[row][col - 1], '|'][above * splitter]
input[row][col + 1] = [input[row][col + 1], '|'][above * splitter]
return above * splitter + t
}, total), 0)
const part2 = input => solve(input, 0, 1, input[0].indexOf('S'))
const input = document.body.innerText.trim().split('\n').map(l => [...l])
console.time('Advent of Code day 7 flowless challenge both parts')
console.log([part1(input.map(r => r.map(c => c))), part2(input)])
console.timeEnd('Advent of Code day 7 flowless challenge both parts')](https://cdn.bsky.app/img/feed_thumbnail/plain/did:plc:imdouboftoohbcdk4tvnlez7/bafkreiafc2k7xwkxi763k55zywdlkvg74fumy3m7ancmlwguhz7rqdvava)
![// My solution for day 6 to this challenge: https://www.reddit.com/r/adventofcode/comments/1p2ral9/flowless_challenge_2025/
// Purely functional and branchless programming
// Just paste this code into the developer console on https://adventofcode.com/2025/day/6/input (try F12 or CTRL+I in your browser)
// The two numbers are the results for the first and second part for your personal input
const transpose = grid => grid.reduce((cols, row, r, arr) =>
[ cols, row.map((_, c) => arr.map(l => l[c])) ][+(r == 0)] , [])
const part1 = input => {
input = input.trim().split('\n').map(l => {
l = l.trim().replace(/ +/g, ' ').split(' ')
return [l, l.map(Number)][+(l[0].match(/\d+/) != null)]
})
const operations = input.pop()
return transpose(input)
.map((vals, i) => [
vals.reduce((acc, cur) => acc * cur, 1),
vals.reduce((acc, cur) => acc + cur, 0)
][+(operations[i] == '+')])
.reduce((acc, cur) => acc + cur, 0)
}
const part2 = input => {
input = transpose(input.trim().split('\n').map(l => l.split('')))
input = input.map(l => l.map(c => [c, ' '][+(typeof c === 'undefined')])).reverse()
return input.reduce(([total, block], line) => {
const op = line.pop()
const val = Number(line.join(''))
block = [[...block, val], block][+(val == 0)]
line = [
0,
block.reduce((a, v) => a + v, 0),
block.reduce((a, v) => a * v, 1)
][' +*'.indexOf(op)]
block = [ block, [], [] ][' +*'.indexOf(op)]
return [total + line, block]
}, [0, []])[0]
}
const db = document.body.innerText
console.time('Advent of Code day 6 flowless challenge both parts')
console.log([part1(db), part2(db)])
console.timeEnd('Advent of Code day 6 flowless challenge both parts')](https://cdn.bsky.app/img/feed_thumbnail/plain/did:plc:imdouboftoohbcdk4tvnlez7/bafkreiadevscuyattbzdg6t4c4kc7izctttx3hielcqtioi2adlc33elre)
![// My solution for day 5 to this challenge: https://www.reddit.com/r/adventofcode/comments/1p2ral9/flowless_challenge_2025/
// Purely functional and branchless programming
// Just paste this code into the developer console on https://adventofcode.com/2025/day/5/input (try F12 or CTRL+I in your browser)
// The two numbers are the results for the first and second part for your personal input
const parseInput = input => {
const [ranges, ing] = input.trim().split('\n\n')
return [
ranges.split('\n').map(l => l.split('-').map(Number)),
ing.split('\n').map(Number)
]
}
const part1 = ([ranges, ings]) => ings.reduce((acc, ing) => acc + ranges.some(([l, h]) => ing >= l && ing <= h), 0)
const part2 = ([ranges]) => {
ranges.sort((a, b) => a[0] - b[0])
return ranges
.reduce((comp, [l, h]) => {
const found = +(comp.some(([s, e], i) => {
const contained = +(s <= l && l < e && e > h)
const extend = +(s <= l && l <= e && e <= h)
comp[i][1] = [e, h][extend]
return contained || extend
}))
return [[...comp, [l, h]], comp][found]
}, [ranges[0]])
.reduce((acc, [l, h]) => acc + h - l + 1, 0)
}
const db = parseInput(document.body.innerText)
console.time('Advent of Code day 5 flowless challenge both parts')
console.log([part1(db), part2(db)])
console.timeEnd('Advent of Code day 5 flowless challenge both parts')](https://cdn.bsky.app/img/feed_thumbnail/plain/did:plc:imdouboftoohbcdk4tvnlez7/bafkreifbf5tjvhf622se5oxk7vn7mt3yqnufbnswoea3a4ayjq5s4gtwuq)
![// My solution for day 4 to this challenge: https://www.reddit.com/r/adventofcode/comments/1p2ral9/flowless_challenge_2025/
// Purely functional and branchless programming
// Just paste this code into the developer console on https://adventofcode.com/2025/day/4/input (try F12 or CTRL+I in your browser)
// The two numbers are the results for the first and second part for your personal input
const eightWayDeltas = [[-1, -1], [-1, 0], [-1, 1], [0, -1], [0, 1], [1, -1], [1, 0], [1, 1]]
const gridCells = grid => grid.reduce((cells, line, row) => [...cells, ...line.map((value, col) => { return {row, col, value} })], [])
const validCoordForGrid = (row, col, grid) => row >= 0 && row < grid.length && col >= 0 && col < grid[row].length
const getSurroundingGridCoords = (grid, row, col, deltas) =>
deltas.flatMap(([r, c]) => Array(+(validCoordForGrid(row + r, col + c, grid))).fill([row + r, col + c]));
const getSurrounding = (grid, row, col, deltas) =>
getSurroundingGridCoords(grid, row, col, deltas).reduce((tiles, [r, c]) => [...tiles, { tile: grid[r][c], row: r, col: c }], [])
const solve = (grid, total, isPart1) => {
let changed = gridCells(grid)
.filter(f => f.value == '@')
.reduce((acc, {row, col}) => {
const removable = +(getSurrounding(grid, row, col, eightWayDeltas).filter(f => f.tile == '@').length < 4)
grid[row][col] = '@.'[removable * !isPart1]
return acc + removable
}, 0)
return ((changed == 0) * total) || (isPart1 * changed) || solve(grid, total + changed, isPart1)
}
const input = document.body.innerText.trim().split('\n').map(l => l.split(''))
console.time('Advent of Code 2025 day 4 both parts')
console.log([
solve(input.map(r => r.map(c => c)), 0, 1),
solve(input.map(r => r.map(c => c)), 0, 0)
])
console.timeEnd('Advent of Code 2025 day 4 both parts')](https://cdn.bsky.app/img/feed_thumbnail/plain/did:plc:imdouboftoohbcdk4tvnlez7/bafkreihonmgnflcpthcdfb6g7f3qohdwm7hmbmbl2ymuantbkeifx5kzsm)
![// My solution for day 3 to this challenge: https://www.reddit.com/r/adventofcode/comments/1p2ral9/flowless_challenge_2025/
// Purely functional and branchless programming
// Just paste this code into the developer console on https://adventofcode.com/2025/day/3/input (try F12 or CTRL+I in your browser)
// The two numbers are the results for the first and second part for your personal input
const best = (digits, row) => Number(
(new Array(digits))
.fill(0)
.reduce(([res, pos, i]) => {
const r = res + Math.max(...row.slice(pos + 1, row.length - digits + 1 + i))
return [ r, pos + row.slice(pos + 1).indexOf(~~r[r.length - 1]) + 1, i + 1 ]
}, ['', -1, 0])[0]
)
console.log(
document.body.innerText
.trim()
.split('\n')
.map(l => l.split('').map(Number))
.reduce(([p1, p2], row) => [p1 + best(2, row), p2 + best(12, row)], [0, 0])
)](https://cdn.bsky.app/img/feed_thumbnail/plain/did:plc:imdouboftoohbcdk4tvnlez7/bafkreifpvlmoej2khbaionsyiqgqao2hgwec522k54kix4berseolqfc2y)
![// My solution for day 2 to this challenge: https://www.reddit.com/r/adventofcode/comments/1p2ral9/flowless_challenge_2025/
// Purely functional and branchless programming
// Just paste this code into the developer console on https://adventofcode.com/2025/day/2/input (try F12 or CTRL+I in your browser)
// The two numbers are the results for the first and second part for your personal input
console.log(
document.body.innerText
.split(',')
.map(range => range.split('-').map(Number))
.reduce(([p1, p2], [start, end]) =>
(new Array(end - start))
.fill(0)
.reduce(([a, b, v]) => [
a + /^(\d+)\1$/.test(v) * v,
b + /^(\d+)\1+$/.test(v) * v,
v + 1
], [p1, p2, start])
, [0, 0])
.slice(0, 2)
)](https://cdn.bsky.app/img/feed_thumbnail/plain/did:plc:imdouboftoohbcdk4tvnlez7/bafkreihf6usrdsnnqxx7pz6qomjfzrtxkdvhncyldflvay3fp72ny4k7ti)
![// My solution to this challenge: https://www.reddit.com/r/adventofcode/comments/1p2ral9/flowless_challenge_2025/
// Purely functional and branchless programming
// Just paste this code into the developer console on https://adventofcode.com/2025/day/1/input (try F12 or CTRL+I in your browser)
// The two numbers are the results for the first and second part for your personal input
console.log(
document.body.innerText
.split('\n')
.map(l => [(l[0] == 'R') * 2 - 1, ~~l.slice(1)])
.reduce(([p1, p2, pos], [dir, val]) => {
[pos, p2] = (new Array(val))
.fill(0)
.reduce(([p, z, d]) => {
p = (p + d + 100) % 100
z += p == 0
return [p, z, d]
}, [pos, p2, dir])
p1 += pos == 0
return [p1, p2, pos]
}, [0, 0, 50])
.slice(0, 2)
)](https://cdn.bsky.app/img/feed_thumbnail/plain/did:plc:imdouboftoohbcdk4tvnlez7/bafkreid3qlej3f4yj6mwn3e4xsok65vco3vhu2an7yjlbyyvdmmbwhufna)
