feat: solve day 11 puzzle 2

.gitignore

@@ -0,0 +1,2 @@
+.vscode
+res/inputs

README.md

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+# Advent of Code
+
+This repo contains my attempt at this year's Advent of Code (2025)
+
+I will solve this AoC using Lua in the context of the ComputerCraft Minecraft mod.\
+This project can also be run using the amazing [CraftOS-PC emulator](https://github.com/MCJack123/craftos2)
+
+## Progress
+
+<!-- calendar-start -->
+#### Stars: 20/24
+
+|Mon|Tue|Wed|Thu|Fri|Sat|Sun|
+|:-:|:-:|:-:|:-:|:-:|:-:|:-:|
+|1<br>:star::star:|2<br>:star::star:|3<br>:star::star:|4<br>:star::star:|5<br>:star::star:|6<br>:star::star:|7<br>:star::star:|
+|8<br>:star::star:|9<br>:star:|10<br>:star:|11<br>:star::star:|12<br>|||
+<!-- calendar-end -->

res/examples/day01.txt

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+L68
+L30
+R48
+L5
+R60
+L55
+L1
+L99
+R14
+L82

res/examples/day02.txt

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+11-22,95-115,998-1012,1188511880-1188511890,222220-222224,
+1698522-1698528,446443-446449,38593856-38593862,565653-565659,
+824824821-824824827,2121212118-2121212124

res/examples/day03.txt

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+987654321111111
+811111111111119
+234234234234278
+818181911112111

res/examples/day04.txt

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+..@@.@@@@.
+@@@.@.@.@@
+@@@@@.@.@@
+@.@@@@..@.
+@@.@@@@.@@
+.@@@@@@@.@
+.@.@.@.@@@
+@.@@@.@@@@
+.@@@@@@@@.
+@.@.@@@.@.

res/examples/day05.txt

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+3-5
+10-14
+16-20
+12-18
+
+1
+5
+8
+11
+17
+32

res/examples/day06.txt

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+123 328  51 64 
+ 45 64  387 23 
+  6 98  215 314
+*   +   *   +  

res/examples/day07.txt

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+.......S.......
+...............
+.......^.......
+...............
+......^.^......
+...............
+.....^.^.^.....
+...............
+....^.^...^....
+...............
+...^.^...^.^...
+...............
+..^...^.....^..
+...............
+.^.^.^.^.^...^.
+...............

res/examples/day08.txt

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+162,817,812
+57,618,57
+906,360,560
+592,479,940
+352,342,300
+466,668,158
+542,29,236
+431,825,988
+739,650,466
+52,470,668
+216,146,977
+819,987,18
+117,168,530
+805,96,715
+346,949,466
+970,615,88
+941,993,340
+862,61,35
+984,92,344
+425,690,689

res/examples/day09.txt

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+7,1
+11,1
+11,7
+9,7
+9,5
+2,5
+2,3
+7,3

res/examples/day10.txt

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+[.##.] (3) (1,3) (2) (2,3) (0,2) (0,1) {3,5,4,7}
+[...#.] (0,2,3,4) (2,3) (0,4) (0,1,2) (1,2,3,4) {7,5,12,7,2}
+[.###.#] (0,1,2,3,4) (0,3,4) (0,1,2,4,5) (1,2) {10,11,11,5,10,5}

res/examples/day11.txt

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+svr: aaa bbb
+aaa: fft
+fft: ccc
+bbb: tty
+tty: ccc
+ccc: ddd eee
+ddd: hub
+hub: fff
+eee: dac
+dac: fff
+fff: ggg hhh
+ggg: out
+hhh: out

res/examples/day11_1.txt

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+aaa: you hhh
+you: bbb ccc
+bbb: ddd eee
+ccc: ddd eee fff
+ddd: ggg
+eee: out
+fff: out
+ggg: out
+hhh: ccc fff iii
+iii: out

res/stats.json

@@ -1,51 +1,50 @@
 {
     "day01": {
-        "puzzle1": false,
+        "puzzle1": true,
-        "puzzle2": false
+        "puzzle2": true
     },
     "day02": {
-        "puzzle1": false,
+        "puzzle1": true,
-        "puzzle2": false
+        "puzzle2": true
     },
     "day03": {
-        "puzzle1": false,
+        "puzzle1": true,
-        "puzzle2": false
+        "puzzle2": true
     },
     "day04": {
-        "puzzle1": false,
+        "puzzle1": true,
-        "puzzle2": false
+        "puzzle2": true
     },
     "day05": {
-        "puzzle1": false,
+        "puzzle1": true,
-        "puzzle2": false
+        "puzzle2": true
     },
     "day06": {
-        "puzzle1": false,
+        "puzzle1": true,
-        "puzzle2": false
+        "puzzle2": true
     },
     "day07": {
-        "puzzle1": false,
+        "puzzle1": true,
-        "puzzle2": false
+        "puzzle2": true
     },
     "day08": {
-        "puzzle1": false,
+        "puzzle1": true,
-        "puzzle2": false
+        "puzzle2": true
     },
     "day09": {
-        "puzzle1": false,
+        "puzzle1": true,
         "puzzle2": false
     },
     "day10": {
-        "puzzle1": false,
+        "puzzle1": true,
         "puzzle2": false
     },
     "day11": {
-        "puzzle1": false,
+        "puzzle1": true,
-        "puzzle2": false
+        "puzzle2": true
     },
     "day12": {
         "puzzle1": false,
         "puzzle2": false
     }
 }
-

src/calendar.lua

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+package.path = "/aoc/src/lib/?.lua;" .. package.path
+require("aoc")
+local json = require("json")
+local utils = require("utils")
+local buffer = require("buffer")
+local stats = json.loads(utils.readFile(RES_PATH .. "/stats.json")) or {}
+local readmePath = ROOT_PATH .. "/README.md"
+local outBuf = buffer.Buffer.new()
+
+local function insertInReadme()
+    local body = utils.readFile(readmePath) or ""
+    local tagStart = "<!-- calendar-start -->"
+    local tagEnd = "<!-- calendar-end -->"
+    body = body:gsub(
+        tagStart:gsub("%-", "%%-") .. ".-" .. tagEnd:gsub("%-", "%%-"),
+        tagStart .. "\n" .. outBuf:tostring() .. tagEnd
+    )
+    utils.writeFile(readmePath, body, true)
+end
+
+local totalStars = 0
+---@diagnostic disable-next-line: param-type-mismatch
+for _, s in pairs(stats) do
+    if s.puzzle1 then totalStars = totalStars + 1 end
+    if s.puzzle2 then totalStars = totalStars + 1 end
+end
+
+local startTS = 1764543600
+
+local startDate = os.date("*t", startTS)
+local firstWeekday = (startDate.wday + 5) % 7
+local padding = {x=3, y=1}
+
+local dayNames = {
+    "Mon", "Tue", "Wed", "Thu", "Fri", "Sat", "Sun"
+}
+
+local day = -firstWeekday + 1
+
+local rowSep = "+"
+local padRow = "|"
+for _ = 1, 7 do
+    rowSep = rowSep .. string.rep("-", padding.x * 2 + 3) .. "+"
+    padRow = padRow .. string.rep(" ", padding.x * 2 + 3) .. "|"
+end
+
+local function printRow(cells, cellWidth, padding)
+    local xPad = string.rep(" ", padding.x)
+    local height = 0
+    for _, cell in ipairs(cells) do
+        height = math.max(height, type(cell) == "string" and 1 or #cell)
+    end
+
+    for i = -padding.y + 1, height + padding.y do
+        write("|")
+        for _, cell in ipairs(cells) do
+            local text = cell[i] or ""
+            if type(cell) == "string" and i == 1 then
+                text = cell
+            end
+            local pad = cellWidth - #text
+            local lPad = math.ceil(pad / 2)
+            local rPad = pad - lPad
+            write(xPad .. string.rep(" ", lPad))
+            if i > 1 and i <= height then
+                term.setTextColor(colors.orange)
+            end
+            write(text)
+            term.setTextColor(colors.white)
+            write(string.rep(" ", rPad) .. xPad .. "|")
+        end
+        print()
+    end
+    print(rowSep)
+end
+
+term.clear()
+term.setCursorPos(1, 1)
+term.setTextColor(colors.white)
+
+print(("Stars: %d/24"):format(totalStars, 24))
+outBuf:print(("#### Stars: %d/24\n"):format(totalStars, 24))
+
+print(rowSep)
+printRow(dayNames, 3, padding)
+
+outBuf:print("|" .. table.concat(dayNames, "|") .. "|")
+for _ = 1, 7 do
+    outBuf:write("|:-:")
+end
+outBuf:print("|")
+
+while day < 12 do
+    local row = {}
+    local outRow = {}
+    for _ = 1, 7 do
+        if day < 1 or day > 12 then
+            table.insert(row, "")
+            table.insert(outRow, "")
+        else
+            local dayStats = stats[("day%02d"):format(day)]
+            local stars = 0
+            if dayStats.puzzle1 then stars = stars + 1 end
+            if dayStats.puzzle2 then stars = stars + 1 end
+            local cell = {
+                tostring(day),
+                string.rep("\x04", stars, " ")
+            }
+            table.insert(row, cell)
+            cell = {
+                tostring(day),
+                string.rep(":star:", stars, "")
+            }
+            table.insert(outRow, table.concat(cell, "<br>"))
+        end
+        day = day + 1
+    end
+    printRow(row, 3, padding)
+    outBuf:print("|" .. table.concat(outRow, "|") .. "|")
+end
+
+insertInReadme()
+
+---@diagnostic disable-next-line: undefined-field
+term.screenshot()
+os.sleep(2)

src/day01/puzzle1.lua

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+local utils = require "utils"
+local puzzle1 = {}
+
+function puzzle1.solve(input)
+    local password = 0
+    local cursor = 50
+    
+    local lines = utils.splitLines(input)
+    for _, line in ipairs(lines) do
+        local dir = line:sub(1, 1)
+        local dist = tonumber(line:sub(2))
+        if dir == "R" then
+            cursor = cursor + dist
+        else
+            cursor = cursor - dist
+        end
+        cursor = cursor % 100
+        if cursor == 0 then
+            password = password + 1
+        end
+    end
+    return password
+end
+
+return puzzle1

src/day01/puzzle2.lua

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+local utils = require "utils"
+local puzzle2 = {}
+
+function puzzle2.solve(input)
+    local password = 0
+    local cursor = 50
+    
+    local lines = utils.splitLines(input)
+    for _, line in ipairs(lines) do
+        local dir = line:sub(1, 1)
+        local dist = tonumber(line:sub(2))
+        if dir == "R" then
+            cursor = cursor + dist
+            if cursor > 99 then
+                password = password + math.floor(cursor / 100)
+            end
+        else
+            cursor = cursor - dist
+            if cursor <= 0 then
+                if cursor ~= -dist then
+                    password = password + 1
+                end
+                password = password + math.floor(-cursor / 100)
+            end
+        end
+        cursor = cursor % 100
+    end
+    return password
+end
+
+return puzzle2

src/day02/puzzle1.lua

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+local utils = require "utils"
+local puzzle1 = {}
+
+function puzzle1.splitRange(range)
+    local parts = utils.split(range, "-")
+    return tonumber(parts[1]), tonumber(parts[2])
+end
+
+function puzzle1.isValid(id)
+    local str = tostring(id)
+    if #str % 2 == 1 then
+        return true
+    end
+    local mid = #str / 2
+    return str:sub(1, mid) ~= str:sub(mid + 1)
+end
+
+function puzzle1.countInvalids(range)
+    local min, max = puzzle1.splitRange(range)
+    local total = 0
+    for i=min, max do
+        if not puzzle1.isValid(i) then
+            total = total + i
+        end
+    end
+    return total
+end
+
+function puzzle1.solve(input)
+    local ranges = utils.split(input, ",")
+    local total = 0
+    for _, range in ipairs(ranges) do
+        total = total + puzzle1.countInvalids(range)
+    end
+    return total
+end
+
+return puzzle1

src/day02/puzzle2.lua

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+local utils = require "utils"
+local puzzle1 = require(SRC_PATH .. "/day02/puzzle1")
+local puzzle2 = {}
+
+function puzzle2.isValid(id)
+    local str = tostring(id)
+    local totLen = #str
+    for len=1, totLen - 1 do
+        if totLen % len == 0 then
+            local ref = str:sub(1, len)
+            local allSame = true
+            for i=1, totLen / len - 1 do
+                if str:sub(len * i + 1, len * (i + 1)) ~= ref then
+                    allSame = false
+                    break
+                end
+            end
+            if allSame then
+                return false
+            end
+        end
+    end
+    return true
+end
+
+function puzzle2.countInvalids(range)
+    local min, max = puzzle1.splitRange(range)
+    local total = 0
+    for i=min, max do
+        if not puzzle2.isValid(i) then
+            total = total + i
+        end
+    end
+    return total
+end
+
+function puzzle2.solve(input)
+    local ranges = utils.split(input, ",")
+    local total = 0
+    for _, range in ipairs(ranges) do
+        total = total + puzzle2.countInvalids(range)
+    end
+    return total
+end
+
+return puzzle2

src/day03/puzzle1.lua

@@ -0,0 +1,41 @@
+local utils = require("utils")
+local puzzle1 = {}
+
+function puzzle1.bankJoltages(bank)
+    local joltages = {}
+    for i=1, #bank do
+        table.insert(joltages, tonumber(bank:sub(i, i)))
+    end
+    return joltages
+end
+
+function puzzle1.findMaxJoltage(bank)
+    local maxTens = 0
+    local maxJoltage = 0
+    local joltages = puzzle1.bankJoltages(bank)
+
+    for i, tens in ipairs(joltages) do
+        if tens > maxTens then
+            for j=i+1, #joltages do
+                local ones = joltages[j]
+                local joltage = tens * 10 + ones
+                if joltage > maxJoltage then
+                    maxTens = tens
+                    maxJoltage = joltage
+                end
+            end
+        end
+    end
+    return maxJoltage
+end
+
+function puzzle1.solve(input)
+    local banks = utils.splitLines(input)
+    local totalJoltage = 0
+    for _, bank in ipairs(banks) do
+        totalJoltage = totalJoltage + puzzle1.findMaxJoltage(bank)
+    end
+    return totalJoltage
+end
+
+return puzzle1

src/day03/puzzle2.lua

@@ -0,0 +1,64 @@
+local utils = require("utils")
+local puzzle1 = require(SRC_PATH .. "/day03/puzzle1")
+local puzzle2 = {}
+
+local cache = {}
+
+function puzzle2.findMaxJoltage(bank, joltages, n, startI)
+    startI = startI or 1
+    local key = bank:sub(startI) .. "-" .. tostring(n)
+    if cache[key] then
+        return cache[key]
+    end
+
+    local maxJoltage = 0
+    local maxDigit = 0
+
+    if startI > #joltages then
+        return nil
+    end
+
+    if n == 1 then
+        for i=startI, #joltages do
+            if joltages[i] > maxDigit then
+                maxDigit = joltages[i]
+            end
+        end
+        cache[key] = maxDigit
+        return maxDigit
+    end
+
+    local i = startI
+    while i <= #joltages do
+        local digit = joltages[i]
+        if digit > maxDigit then
+            local maxSuffix = puzzle2.findMaxJoltage(bank, joltages, n - 1, i + 1)
+            if maxSuffix ~= nil then
+                local joltage = tonumber(tostring(digit) .. tostring(maxSuffix))
+                if joltage > maxJoltage then
+                    maxDigit = digit
+                    maxJoltage = joltage
+                end
+            end
+        end
+        i = i + 1
+    end
+    if maxJoltage == 0 then
+        return nil
+    end
+    cache[key] = maxJoltage
+    return maxJoltage
+end
+
+function puzzle2.solve(input)
+    local banks = utils.splitLines(input)
+    local totalJoltage = 0
+    for _, bank in ipairs(banks) do
+        local joltages = puzzle1.bankJoltages(bank)
+        local max = puzzle2.findMaxJoltage(bank, joltages, 12)
+        totalJoltage = totalJoltage + max
+    end
+    return totalJoltage
+end
+
+return puzzle2

src/day04/puzzle1.lua

@@ -0,0 +1,44 @@
+local utils = require "utils"
+
+local puzzle1 = {}
+
+function puzzle1.inGrid(x, y, w, h)
+    return 1 <= x and x <= w and 1 <= y and y <= h
+end
+
+function puzzle1.isAccessible(lines, w, h, x, y)
+    local neighbors = 0
+    for dy=-1, 1 do
+        for dx=-1, 1 do
+            if dx ~=0 or dy ~= 0 then
+                local x2 = x + dx
+                local y2 = y + dy
+                if puzzle1.inGrid(x2, y2, w, h) then
+                    if lines[y2]:sub(x2, x2) == "@" then
+                        neighbors = neighbors + 1
+                    end
+                end
+            end
+        end
+    end
+    return neighbors < 4
+end
+
+function puzzle1.solve(input)
+    local lines = utils.splitLines(input)
+    local accessible = 0
+
+    local h = #lines
+    local w = #lines[1]
+
+    for y, line in ipairs(lines) do
+        for x=1, #line do
+            if line:sub(x, x) == "@" and puzzle1.isAccessible(lines, w, h, x, y) then
+                accessible = accessible + 1
+            end
+        end
+    end
+    return accessible
+end
+
+return puzzle1

src/day04/puzzle2.lua

@@ -0,0 +1,106 @@
+local utils = require "utils"
+
+local puzzle2 = {}
+
+function puzzle2.inGrid(x, y, w, h)
+    return 1 <= x and x <= w and 1 <= y and y <= h
+end
+
+function puzzle2.countNeighbors(lines, w, h, x, y)
+    local neighbors = 0
+    for dy=-1, 1 do
+        for dx=-1, 1 do
+            if dx ~=0 or dy ~= 0 then
+                local x2 = x + dx
+                local y2 = y + dy
+                if puzzle2.inGrid(x2, y2, w, h) then
+                    if lines[y2]:sub(x2, x2) == "@" then
+                        neighbors = neighbors + 1
+                    end
+                end
+            end
+        end
+    end
+    return neighbors
+end
+
+function puzzle2.copyGrid(grid)
+    local grid2 = {}
+    for y, row in ipairs(grid) do
+        local row2 = {}
+        for x, n in ipairs(row) do
+            row2[x] = n
+        end
+        grid2[y] = row2
+    end
+    return grid2
+end
+
+function puzzle2.removeRoll(grid, x, y, w, h)
+    for dy=-1, 1 do
+        for dx=-1, 1 do
+            if dx ~= 0 or dy ~= 0 then
+                local x2 = x + dx
+                local y2 = y + dy
+                if puzzle2.inGrid(x2, y2, w, h) then
+                    if grid[y2][x2] > 0 then
+                        grid[y2][x2] = grid[y2][x2] - 1
+                    end
+                end
+            end
+        end
+    end
+    grid[y][x] = -1
+end
+
+function puzzle2.removeRolls(grid, w, h)
+    local removed = 0
+    local grid2 = puzzle2.copyGrid(grid)
+
+    for y, row in ipairs(grid) do
+        for x, n in ipairs(row) do
+            if 0 <= n and n < 4 then
+                puzzle2.removeRoll(grid2, x, y, w, h)
+                removed = removed + 1
+            end
+        end
+    end
+
+    return removed, grid2
+end
+
+function puzzle2.solve(input)
+    local lines = utils.splitLines(input)
+
+    local h = #lines
+    local w = #lines[1]
+
+    local grid = {}
+
+    for y, line in ipairs(lines) do
+        local row = {}
+        for x=1, #line do
+            local neighbors = -1
+            if line:sub(x, x) == "@" then
+                neighbors = puzzle2.countNeighbors(lines, w, h, x, y)
+            end
+            row[x] = neighbors
+        end
+        grid[y] = row
+    end
+
+    local totalRemoved = 0
+
+    local removed = 0
+    while true do
+        removed, grid = puzzle2.removeRolls(grid, w, h)
+        if removed == 0 then
+            break
+        end
+        totalRemoved = totalRemoved + removed
+    end
+
+    return totalRemoved
+end
+
+return puzzle2

src/day05/puzzle1.lua

@@ -0,0 +1,39 @@
+local strings = require "cc.strings"
+local puzzle1 = {}
+
+function puzzle1.isFresh(ranges, i)
+    for _, range in ipairs(ranges) do
+        if range[1] <= i and i <= range[2] then
+            return true
+        end
+    end
+    return false
+end
+
+function puzzle1.solve(input)
+    local lines = strings.split(input, "\n")
+    local ranges = {}
+
+    local bIngr = false
+    local totalFresh = 0
+
+    for _, line in ipairs(lines) do
+        if line == "" then
+            bIngr = true
+        else
+            if bIngr then
+                local ingr = tonumber(line)
+                if puzzle1.isFresh(ranges, ingr) then
+                    totalFresh = totalFresh + 1
+                end
+            else
+                local min, max = line:match("(%d+)%-(%d+)")
+                table.insert(ranges, {tonumber(min), tonumber(max)})
+            end
+        end
+    end
+
+    return totalFresh
+end
+
+return puzzle1

src/day05/puzzle2.lua

@@ -0,0 +1,47 @@
+local strings = require "cc.strings"
+local puzzle2 = {}
+
+function puzzle2.solve(input)
+    local lines = strings.split(input, "\n")
+    local bounds = {}
+
+    for _, line in ipairs(lines) do
+        if line == "" then
+            break
+        end
+        local min, max = line:match("(%d+)%-(%d+)")
+        min = tonumber(min)
+        max = tonumber(max)
+        table.insert(bounds, {i=min, type="start"})
+        table.insert(bounds, {i=max, type="end"})
+    end
+
+    table.sort(bounds, function (a, b)
+        if a.i == b.i then
+            return a.type == "start" and b.type == "end"
+        end
+        return a.i < b.i
+    end)
+
+    local totalFresh = 0
+    local min = 0
+    local balance = 0
+
+    for _, bound in ipairs(bounds) do
+        if bound.type == "start" then
+            if balance == 0 then
+                min = bound.i
+            end
+            balance = balance + 1
+        else
+            balance = balance - 1
+            if balance == 0 then
+                totalFresh = totalFresh + bound.i - min + 1
+            end
+        end
+    end
+
+    return totalFresh
+end
+
+return puzzle2

src/day06/puzzle1.lua

@@ -0,0 +1,39 @@
+local strings = require "cc.strings"
+local puzzle1 = {}
+
+function puzzle1.solve(input)
+    local lines = strings.split(input, "\n")
+    local problems = {}
+    local n = #lines
+
+    local ops = strings.split(lines[n], "%s+")
+
+    for i, line in ipairs(lines) do
+        local j = 1
+        for num in line:gmatch("(%d+)") do
+            local op = ops[j]
+            if i == 1 then
+                if op == "+" then
+                    table.insert(problems, 0)
+                else
+                    table.insert(problems, 1)
+                end
+            end
+            local val = tonumber(num)
+            if op == "+" then
+                problems[j] = problems[j] + val
+            else
+                problems[j] = problems[j] * val
+            end
+            j = j + 1
+        end
+    end
+
+    local total = 0
+    for _, val in ipairs(problems) do
+        total = total + val
+    end
+    return total
+end
+
+return puzzle1

src/day06/puzzle2.lua

@@ -0,0 +1,58 @@
+local strings = require "cc.strings"
+local puzzle2 = {}
+
+function puzzle2.parseNumbers(lines)
+    local numbers = {}
+    local n = #lines
+
+    for i, line in ipairs(lines) do
+        if i ~= n then
+            for j=1, #line do
+                local c = line:sub(j, j)
+                if #numbers < j then
+                    table.insert(numbers, {})
+                end
+                if c ~= " " then
+                    table.insert(numbers[j], c)
+                end
+            end
+        end
+    end
+
+    local problems = {{}}
+    for _, num in ipairs(numbers) do
+        if #num == 0 then
+            table.insert(problems, {})
+        else
+            local value = tonumber(table.concat(num, ""))
+            table.insert(problems[#problems], value)
+        end
+    end
+    return problems
+end
+
+function puzzle2.solve(input)
+    local lines = strings.split(input, "\n")
+    local values = puzzle2.parseNumbers(lines)
+    local ops = strings.split(lines[#lines], "%s+")
+
+    local total = 0
+    for p, numbers in ipairs(values) do
+        local op = ops[p]
+        local value = 0
+        if op == "*" then
+            value = 1
+        end
+        for _, num in ipairs(numbers) do
+            if op == "+" then
+                value = value + num
+            else
+                value = value * num
+            end
+        end
+        total = total + value
+    end
+    return total
+end
+
+return puzzle2

src/day07/puzzle1.lua

@@ -0,0 +1,34 @@
+local utils = require "utils"
+
+local puzzle1 = {}
+
+function puzzle1.solve(input)
+    local lines = utils.splitLines(input)
+
+    local beams = {}
+    local totalSplits = 0
+
+    for i, line in ipairs(lines) do
+        local newBeams = {}
+        if i == 1 then
+            newBeams[line:find("S")] = true
+        else
+            for j=1, #line do
+                if beams[j] then
+                    if line:sub(j, j) == "^" then
+                        totalSplits = totalSplits + 1
+                        newBeams[j - 1] = true
+                        newBeams[j + 1] = true
+                    else
+                        newBeams[j] = true
+                    end
+                end
+            end
+        end
+        beams = newBeams
+    end
+
+    return totalSplits
+end
+
+return puzzle1

src/day07/puzzle2.lua

@@ -0,0 +1,37 @@
+local utils = require "utils"
+
+local puzzle2 = {}
+
+function puzzle2.solve(input)
+    local lines = utils.splitLines(input)
+
+    local beams = {}
+
+    for i, line in ipairs(lines) do
+        local newBeams = {}
+        if i == 1 then
+            newBeams[line:find("S")] = 1
+        else
+            for j=1, #line do
+                if beams[j] then
+                    if line:sub(j, j) == "^" then
+                        newBeams[j - 1] = (newBeams[j - 1] or 0) + beams[j]
+                        newBeams[j + 1] = (newBeams[j + 1] or 0) + beams[j]
+                    else
+                        newBeams[j] = (newBeams[j] or 0) + beams[j]
+                    end
+                end
+            end
+        end
+        beams = newBeams
+    end
+
+    local finalBeams = 0
+    for _, v in pairs(beams) do
+        finalBeams = finalBeams + v
+    end
+
+    return finalBeams
+end
+
+return puzzle2

src/day08/puzzle1.lua

@@ -0,0 +1,82 @@
+local utils = require "utils"
+local puzzle1 = {}
+
+function puzzle1.dist(box1, box2)
+    return math.sqrt(
+        (box2.x - box1.x) ^ 2 +
+        (box2.y - box1.y) ^ 2 +
+        (box2.z - box1.z) ^ 2
+    )
+end
+
+function puzzle1.pretty(box)
+    return ("%d,%d,%d"):format(box.x, box.y, box.z)
+end
+
+function puzzle1.solve(input)
+    local boxes = {}
+
+    local lines = utils.splitLines(input)
+
+    for i, line in ipairs(lines) do
+        local x, y, z = line:match("(%d+),(%d+),(%d+)")
+        table.insert(boxes, {x=x, y=y, z=z, i=i, circuit=i})
+    end
+
+    local dists = {}
+    local circuits = {}
+
+    for i, box1 in ipairs(boxes) do
+        circuits[i] = i
+        for j=i+1, #boxes do
+            local box2 = boxes[j]
+            table.insert(dists, {
+                i=i,
+                j=j,
+                dist=puzzle1.dist(box1, box2)
+            })
+        end
+    end
+
+    table.sort(dists, function (a, b)
+        return a.dist < b.dist
+    end)
+
+    local N = 1000
+    if #boxes < 100 then
+        N = 10
+    end
+
+    for i, d in ipairs(dists) do
+        if i > N then
+            break
+        end
+        local circ1 = circuits[d.i]
+        local circ2 = circuits[d.j]
+
+        for k, v in pairs(circuits) do
+            if v == circ2 then
+                circuits[k] = circ1
+            end
+        end
+    end
+
+    local circuitSizes = {}
+
+    for _, c in pairs(circuits) do
+        circuitSizes[c] = (circuitSizes[c] or 0) + 1
+    end
+
+    local sizes = {}
+
+    for _, s in pairs(circuitSizes) do
+        table.insert(sizes, s)
+    end
+
+    table.sort(sizes)
+    local n = #sizes
+
+    return sizes[n] * sizes[n - 1] * sizes[n - 2]
+end
+
+return puzzle1

src/day08/puzzle2.lua

@@ -0,0 +1,52 @@
+local utils = require "utils"
+local puzzle1 = require(SRC_PATH .. "/day08/puzzle1")
+local puzzle2 = {}
+
+function puzzle2.solve(input)
+    local boxes = {}
+
+    local lines = utils.splitLines(input)
+
+    for i, line in ipairs(lines) do
+        local x, y, z = line:match("(%d+),(%d+),(%d+)")
+        table.insert(boxes, {x=x, y=y, z=z, i=i, circuit=i})
+    end
+
+    local dists = {}
+    local circuits = {}
+
+    for i, box1 in ipairs(boxes) do
+        circuits[i] = i
+        for j=i+1, #boxes do
+            local box2 = boxes[j]
+            table.insert(dists, {
+                i=i,
+                j=j,
+                dist=puzzle1.dist(box1, box2)
+            })
+        end
+    end
+
+    table.sort(dists, function (a, b)
+        return a.dist < b.dist
+    end)
+
+    for _, d in ipairs(dists) do
+        local circ1 = circuits[d.i]
+        local circ2 = circuits[d.j]
+        
+        local connex = true
+        for k, v in pairs(circuits) do
+            if v == circ2 then
+                circuits[k] = circ1
+            elseif v ~= circ1 then
+                connex = false
+            end
+        end
+        if connex then
+            return boxes[d.i].x * boxes[d.j].x
+        end
+    end
+end
+
+return puzzle2

src/day09/puzzle1.lua

@@ -0,0 +1,30 @@
+local utils = require "utils"
+local puzzle1 = {}
+
+function puzzle1.area(tile1, tile2)
+    local dx = math.abs(tile2.x - tile1.x) + 1
+    local dy = math.abs(tile2.y - tile1.y) + 1
+    return dx * dy
+end
+
+function puzzle1.solve(input)
+    local lines = utils.splitLines(input)
+    local tiles = {}
+
+    for _, line in ipairs(lines) do
+        local x, y = line:match("(%d+),(%d+)")
+        table.insert(tiles, {x=tonumber(x), y=tonumber(y)})
+    end
+
+    local maxArea = 0
+    for i, tile1 in ipairs(tiles) do
+        for j=i+1, #tiles do
+            local tile2 = tiles[j]
+            local area = puzzle1.area(tile1, tile2)
+            maxArea = math.max(maxArea, area)
+        end
+    end
+    return maxArea
+end
+
+return puzzle1

src/day09/puzzle2.lua

@@ -0,0 +1,7 @@
+local puzzle2 = {}
+
+function puzzle2.solve(input)
+    return 0
+end
+
+return puzzle2

src/day10/puzzle1.lua

@@ -0,0 +1,88 @@
+local strings = require "cc.strings"
+local utils = require "utils"
+local puzzle1 = {}
+
+function puzzle1.parseMachine(line)
+    local lightsStr = line:match("%[([.#]+)%]")
+    local buttonsStr = strings.split(line:match(" (.+) "), " ")
+
+    local lightsBools = {}
+    local lightsVal = 0
+    for i=1, #lightsStr do
+        local c = lightsStr:sub(i, i)
+        lightsBools[i] = c == "#"
+        if c == "#" then
+            local pow = bit.blshift(1, i - 1)
+            lightsVal = lightsVal + pow
+        end
+    end
+
+    local buttons = {}
+
+    for _, btnStr in ipairs(buttonsStr) do
+        local lights = {}
+        local value = 0
+        for n in btnStr:gmatch("%d+") do
+            local v = tonumber(n)
+            table.insert(lights, v)
+            value = value + bit.blshift(1, v)
+        end
+        table.insert(buttons, {
+            lights=lights,
+            value=value,
+            presses=0
+        })
+    end
+
+    return {
+        lightsBools=lightsBools,
+        lightsVal=lightsVal,
+        buttons=buttons
+    }
+end
+
+function puzzle1.startMachine(target, btns)
+    local queue = {{value=0, presses=0, used=0}}
+    local cache = {}
+    while #queue ~= 0 do
+        local test = table.remove(queue, 1)
+        local key = tostring(test.value) .. "-" .. tostring(test.used)
+        if not cache[key] then
+            cache[key] = true
+            if test.value == target then
+                return test.presses
+            end
+            for i=(test.presses + 1), #btns do
+                local pow = bit.blshift(1, i - 1)
+                if bit.band(test.used, pow) == 0 then
+                    table.insert(queue, {
+                        value=bit.bxor(test.value, btns[i].value),
+                        presses=test.presses + 1,
+                        used=test.used + pow
+                    })
+                end
+            end
+        end
+    end
+    print("Could not find valid button combination")
+    return -1
+end
+
+function puzzle1.solve(input)
+    local lines = utils.splitLines(input)
+    local machines = {}
+    for _, line in ipairs(lines) do
+        table.insert(machines, puzzle1.parseMachine(line))
+    end
+
+    local totalPresses = 0
+
+    for i, machine in ipairs(machines) do
+        print("Machine " .. tostring(i) .. "/" .. tostring(#machines))
+        totalPresses = totalPresses + puzzle1.startMachine(machine.lightsVal, machine.buttons)
+    end
+
+    return totalPresses
+end
+
+return puzzle1

src/day10/puzzle2.lua

@@ -0,0 +1,7 @@
+local puzzle2 = {}
+
+function puzzle2.solve(input)
+    return 0
+end
+
+return puzzle2

src/day11/puzzle1.lua

@@ -0,0 +1,36 @@
+local strings = require "cc.strings"
+local utils = require "utils"
+local puzzle1 = {}
+
+local cache = {}
+
+function puzzle1.countPaths(edges, startDev, endDev)
+    local key = startDev .. "-" .. endDev
+    if cache[key] then
+        return cache[key]
+    end
+    if startDev == endDev then
+        return 1
+    end
+    local outs = edges[startDev]
+    local total = 0
+    for _, out in ipairs(outs) do
+        total = total + puzzle1.countPaths(edges, out, endDev)
+    end
+    cache[key] = total
+    return total
+end
+
+function puzzle1.solve(input)
+    local lines = utils.splitLines(input)
+    local outputs = {}
+
+    for _, line in ipairs(lines) do
+        local device, outs = line:match("(.+): (.+)")
+        outputs[device] = strings.split(outs, " ")
+    end
+
+    return puzzle1.countPaths(outputs, "you", "out")
+end
+
+return puzzle1

src/day11/puzzle2.lua

@@ -0,0 +1,49 @@
+local strings = require "cc.strings"
+local utils = require "utils"
+local puzzle2 = {}
+
+local cache = {}
+
+function puzzle2.countPaths(edges, startDev, endDev, dac, fft)
+    dac = dac or false
+    fft = fft or false
+    local key = startDev .. "-" .. endDev .. "-" .. tostring(dac) .. "-" .. tostring(fft)
+    if cache[key] then
+        return cache[key]
+    end
+    if startDev == endDev then
+        if dac and fft then
+            return 1
+        else
+            return 0
+        end
+    end
+    local outs = edges[startDev]
+    local total = 0
+    for _, out in ipairs(outs) do
+        local dac2 = dac
+        local fft2 = fft
+        if out == "dac" then
+            dac2 = true
+        elseif out == "fft" then
+            fft2 = true
+        end
+        total = total + puzzle2.countPaths(edges, out, endDev, dac2, fft2)
+    end
+    cache[key] = total
+    return total
+end
+
+function puzzle2.solve(input)
+    local lines = utils.splitLines(input)
+    local outputs = {}
+
+    for _, line in ipairs(lines) do
+        local device, outs = line:match("(.+): (.+)")
+        outputs[device] = strings.split(outs, " ")
+    end
+
+    return puzzle2.countPaths(outputs, "svr", "out")
+end
+
+return puzzle2

src/lib/aoc.lua

@@ -1,5 +1,7 @@
-SRC_PATH = "/aoc/src"
+ROOT_PATH = "/aoc"
-RES_PATH = "/aoc/res"
+SRC_PATH = ROOT_PATH .. "/src"
+RES_PATH = ROOT_PATH .. "/res"
+CACHE_PATH = "/.cache/aoc"
 
 package.path = SRC_PATH .. "/lib/?.lua;" .. package.path
 
@@ -9,25 +11,17 @@ END_DATE = {day=12, month=12, year=2025}
 local json = require("json")
 local dates = require("dates")
 local days = require("days")
+local utils = require("utils")
+local progress = require "progress"
 local today = os.date("*t")
+local aoc = {}
 
-local function loadStats(path)
+function aoc.loadStats()
-    path = shell.resolve(path)
+    local data = utils.readFile(RES_PATH .. "/stats.json") or "{}"
-    if not fs.exists(path) then
+    return json.loads(data)
-        printError("Stats file not found (" .. path .. ")")
-        return
-    end
-    local file, err = fs.open(path, "r")
-    if not file then
-        printError("Cannot open stats file")
-        return
-    end
-    local data = json.loads(file.readAll())
-    file.close()
-    return data
 end
 
-local function printDateInfo()
+function aoc.printDateInfo()
     if dates.isBefore(START_DATE, today) then
         print("AoC 2025 has not started yet")
         return
@@ -40,7 +34,7 @@ local function printDateInfo()
     print("Day " .. day .. "/" .. END_DATE.day)
 end
 
-local function printStats(stats, selected)
+function aoc.printStats(stats, selected)
     local keys = {}
     for k in pairs(stats) do
         table.insert(keys, k)
@@ -55,43 +49,50 @@ local function printStats(stats, selected)
         local date = {day=day, month=START_DATE.month, year=START_DATE.year}
         term.setTextColor(colors.lightBlue)
         if selected == day then
+            term.setBackgroundColor(colors.gray)
             write("- ")
         else
+            term.setBackgroundColor(colors.black)
             write("  ")
         end
         if not dates.isBefore(date, today) then
             term.setTextColor(colors.white)
         else
-            term.setTextColor(colors.gray)
+            term.setTextColor(colors.lightGray)
         end
         write(string.format("Day %2s ", day))
         if value.puzzle1 then
             term.setTextColor(colors.orange)
             stars = stars + 1
         else
-            term.setTextColor(colors.gray)
+            term.setTextColor(colors.lightGray)
         end
         write("\x04")
         if value.puzzle2 then
             term.setTextColor(colors.orange)
             stars = stars + 1
         else
-            term.setTextColor(colors.gray)
+            term.setTextColor(colors.lightGray)
         end
         write("\x04")
         term.setTextColor(colors.white)
-        print()
+        print(" ")
     end
+    term.setBackgroundColor(colors.black)
 
     term.setTextColor(colors.white)
     write(string.format("You have %d", stars))
     term.setTextColor(colors.orange)
-    write("\x04")
+    write("\x04  ")
+    local x, y = term.getCursorPos()
+    progress.bar(x, y, 20, stars, 24, colors.orange, colors.gray)
     term.setTextColor(colors.white)
     print()
+    print()
+    print("Press END to quit")
 end
 
-local function printBanner()
+function aoc.printBanner()
     term.setTextColor(colors.green)
     print("+--------------------------------------+")
     print("|  Welcome to the Advent of Code 2025  |")
@@ -99,8 +100,8 @@ local function printBanner()
     term.setTextColor(colors.white)
 end
 
-local function main()
+function aoc.main()
-    local stats = loadStats("aoc/res/stats.json")
+    local stats = aoc.loadStats() or {}
     local selectedDay = math.max(1, math.min(END_DATE.day, today.day))
     if not dates.isInDateRange(START_DATE, today, END_DATE) then
         selectedDay = 1
@@ -109,9 +110,9 @@ local function main()
     while true do
         term.clear()
         term.setCursorPos(1, 1)
-        printBanner()
+        aoc.printBanner()
-        printDateInfo()
+        aoc.printDateInfo()
-        printStats(stats, selectedDay)
+        aoc.printStats(stats, selectedDay)
 
         local event, key, is_held = os.pullEvent("key")
         if key == keys.up then
@@ -128,8 +129,9 @@ local function main()
                 dayStats.puzzle2
             )
             day:show()
+            stats = aoc.loadStats() or {}
         end
     end
 end
 
-main()
+return aoc

src/lib/buffer.lua

@@ -0,0 +1,35 @@
+local buffer = {}
+
+---@class Buffer
+local Buffer = {_buf=""}
+Buffer.__index = Buffer
+
+---Creates a new buffer
+---@param str string?
+---@return Buffer
+function Buffer.new(str)
+    local buf = {}
+    buf._buf = str or ""
+    setmetatable(buf, Buffer)
+    return buf
+end
+
+function Buffer:tostring()
+    return self._buf
+end
+
+function Buffer:clear()
+    self._buf = ""
+end
+
+function Buffer:write(text)
+    self._buf = self._buf .. (text or "")
+end
+
+function Buffer:print(text)
+    self:write((text or "") .. "\n")
+end
+
+buffer.Buffer = Buffer
+
+return buffer

src/lib/days.lua

@@ -1,14 +1,8 @@
+local json = require("json")
 local utils = require("utils")
 local days = {}
 
-local DAY_CACHE_PATH = "/.cache/days"
+local DAY_CACHE_PATH = CACHE_PATH .. "/days"
-
-local CHOICES = {
-    create = "Create files",
-    example = "Run examples",
-    real = "Run with real input",
-    main = "Back to main menu"
-}
 
 local PUZZLE_BASE = [[local puzzle%d = {}
 
@@ -24,7 +18,8 @@ return puzzle%d
 ---@field title string?
 ---@field puzzle1 boolean
 ---@field puzzle2 boolean
-local Day = {day = 0, title = nil, puzzle1 = false, puzzle2 = false}
+---@field results table
+local Day = {day = 0, title = nil, puzzle1 = false, puzzle2 = false, results={}}
 Day.__index = Day
 
 ---Creates a new Day object
@@ -38,9 +33,14 @@ function Day.new(dayI, puzzle1, puzzle2)
     day.day = dayI
     day.puzzle1 = puzzle1
     day.puzzle2 = puzzle2
+    day:loadResults()
     return day
 end
 
+function Day:cacheDir()
+    return DAY_CACHE_PATH .. ("/%02d"):format(self.day)
+end
+
 ---Returns the title of this day.
 ---
 ---This function looks in the following places, in order:
@@ -52,7 +52,7 @@ function Day:getTitle()
     if self.title then
         return self.title
     end
-    local cachePath = DAY_CACHE_PATH .. ("/%02d.txt"):format(self.day)
+    local cachePath = self:cacheDir() .. "/name.txt"
     if fs.exists(cachePath) then
         local cache = fs.open(cachePath, "r")
         if cache then
@@ -64,8 +64,8 @@ function Day:getTitle()
             end
         end
     end
-    fs.makeDir(DAY_CACHE_PATH)
+    fs.makeDir(self:cacheDir())
-    local res = http.get("https://adventofcode.com/2024/day/" .. self.day)
+    local res = http.get("https://adventofcode.com/2025/day/" .. self.day)
     local title = "Day " .. self.day
     if res then
         local body = res.readAll() or ""
@@ -125,31 +125,119 @@ function Day:getInputData()
     return utils.readFile(self:inputPath())
 end
 
-function Day:execPuzzle(puzzleI, data)
+function Day:getResultKey(real, puzzle, suffix)
-    local puzzle = require(self:srcDir() .. "/puzzle" .. puzzleI)
+    local key = ""
+    if real then
+        key = "input"
+    else
+        key = "example"
+        if suffix then
+            key = key .. "_" .. suffix
+        end
+    end
+    key = key .. "-" .. puzzle
+    return key
+end
+
+function Day:execPuzzle(puzzleI, data, resultKey)
+    local path = self:srcDir() .. "/puzzle" .. puzzleI
+    package.loaded[path] = nil
+    local puzzle = require(path)
     local t0 = os.epoch("local")
     local result = puzzle.solve(data)
     local t1 = os.epoch("local")
     print(("(Executed in %.3fs)"):format((t1 - t0) / 1000))
-    print("Result:", result)
+    print(("Result: %.0f"):format(result))
+    self.results[resultKey] = result
+    self:saveResults()
 end
 
 function Day:execExample(puzzleI, suffix)
     local data = self:getExampleData(suffix)
-    return self:execPuzzle(puzzleI, data)
+    return self:execPuzzle(puzzleI, data, self:getResultKey(false, puzzleI, suffix))
 end
 
 function Day:execReal(puzzleI)
     local data = self:getInputData()
-    return self:execPuzzle(puzzleI, data)
+    return self:execPuzzle(puzzleI, data, self:getResultKey(true, puzzleI))
 end
 
-function Day:choosePuzzle()
+function Day:choosePuzzle(real)
     self:printTitle()
-    local c = utils.promptChoices({"Puzzle 1", "Puzzle 2", "Back"})
+    local choices = {
+        {"Puzzle 1", 1},
+        {"Puzzle 2", 2},
+        "Back"
+    }
+    local res1 = self.results[self:getResultKey(real, 1)]
+    local res2 = self.results[self:getResultKey(real, 2)]
+    if res1 then choices[1][1] = choices[1][1] .. (" - %s"):format(res1) end
+    if res2 then choices[2][1] = choices[2][1] .. (" - %s"):format(res2) end
+    local c = utils.promptChoices(choices)
     return c
 end
 
+function Day:menuStars()
+    local solvedTxt = function (b)
+        if b then
+            return "solved"
+        end
+        return "unsolved"
+    end
+    local c0 = 1
+    while true do
+        self:printTitle()
+        local choices = {
+            {"Mark puzzle 1 as " .. solvedTxt(not self.puzzle1), 1},
+            {"Mark puzzle 2 as " .. solvedTxt(not self.puzzle2), 2},
+            "Back"
+        }
+        local c = utils.promptChoices(choices, c0)
+        if c == "Back" then
+            return
+        end
+        c0 = c
+        if c == 1 then
+            self.puzzle1 = not self.puzzle1
+        elseif c == 2 then
+            self.puzzle2 = not self.puzzle2
+        end
+        self:saveStats()
+    end
+end
+
+function Day:saveStats()
+    local path = RES_PATH .. "/stats.json"
+    local content = utils.readFile(path) or "{}"
+    local data = json.loads(content) or {}
+    data[("day%02d"):format(self.day)] = {
+        puzzle1=self.puzzle1,
+        puzzle2=self.puzzle2,
+    }
+    content = json.dumps(data, 4, true)
+    utils.writeFile(path, content, true)
+end
+
+function Day:loadResults()
+    local path = self:cacheDir() .. "/results.json"
+    local results = {}
+    if fs.exists(path) then
+        local data = utils.readFile(path)
+        local r = json.loads(data)
+        if type(r) == "table" then
+            results = r
+        end
+    end
+    self.results = results
+end
+
+function Day:saveResults()
+    local data = json.dumps(self.results)
+    fs.makeDir(self:cacheDir())
+    local path = self:cacheDir() .. "/results.json"
+    utils.writeFile(path, data, true)
+end
+
 function Day:printTitle()
     term.clear()
     term.setCursorPos(1, 1)
@@ -163,28 +251,35 @@ function Day:show()
     while true do
         self:printTitle()
         if fs.exists(self:srcDir()) then
-            local c = utils.promptChoices({CHOICES.example, CHOICES.real, CHOICES.main})
+            local c = utils.promptChoices({
-            if c == CHOICES.main then
+                {"Run examples", "examples"},
+                {"Run with real input", "inputs"},
+                {"Mark solved", "stars"},
+                {"Back to main menu", "main"}
+            })
+            if c == "main" then
                 return
-            end
+            elseif c == "stars" then
-            local puzzle = self:choosePuzzle()
+                self:menuStars()
+            else
+                local puzzle = self:choosePuzzle(c == "inputs")
                 if puzzle ~= "Back" then
-                local puzzleI = ({
+                    if c == "examples" then
-                    ["Puzzle 1"] = 1,
+                        self:execExample(puzzle)
-                    ["Puzzle 2"] = 2
+                    elseif c == "inputs" then
-                })[puzzle]
+                        self:execReal(puzzle)
-                if c == CHOICES.example then
-                    self:execExample(puzzleI)
-                elseif c == CHOICES.real then
-                    self:execReal(puzzleI)
                     end
                     utils.waitForKey(keys.enter)
                 end
+            end
         else
-            local c = utils.promptChoices({CHOICES.create, CHOICES.main})
+            local c = utils.promptChoices({
-            if c == CHOICES.main then
+                {"Create files", "create"},
+                {"Back to main menu", "main"}
+            })
+            if c == "main" then
                 return
-            elseif c == CHOICES.create then
+            elseif c == "create" then
                 self:createFiles()
             end
         end

src/lib/json.lua

@@ -20,6 +20,13 @@ local function errFactory(prefix)
     end
 end
 
+local function ifNil(test, ifNil, ifNotNil)
+    if test == nil then
+        return ifNil
+    end
+    return ifNotNil
+end
+
 local function parseObj(data)
     local printErr = errFactory("Error while parsing object")
     local obj = {}
@@ -199,4 +206,86 @@ function json.loads(data)
     return res
 end
 
+local function kind(obj)
+    if type(obj) ~= "table" then
+        return type(obj)
+    end
+    local i = 1
+    for _ in pairs(obj) do
+        if obj[i] ~= nil then
+            i = i + 1
+        else
+            return "table"
+        end
+    end
+    if i == 1 then
+        return "table"
+    end
+    return "array"
+end
+
+local function escapeStr(str)
+    local in_char  = {'\\', '"', '/', '\b', '\f', '\n', '\r', '\t'}
+    local out_char = {'\\', '"', '/',  'b',  'f',  'n',  'r',  't'}
+    for i, c in ipairs(in_char) do
+        str = str:gsub(c, '\\' .. out_char[i])
+    end
+    return str
+end
+
+function json.dumps(data, indent, sortKeys, depth)
+    if data == json.null then
+        return "null"
+    end
+
+    local t = kind(data)
+    if t == "string" then
+        return '"' .. escapeStr(data) .. '"'
+    elseif t == "number" or t == "boolean" then
+        return tostring(data)
+    end
+
+    depth = depth or 0
+    local spaces = ""
+    if indent ~= nil then
+        spaces = string.rep(" ", indent * depth)
+    end
+    local res = ""
+
+    if t == "array" then
+        res = res .. "[" .. ifNil(indent, "", "\n")
+        for i, val in ipairs(data) do
+            if i > 1 then
+                res = res .. "," .. ifNil(indent, " ", "\n")
+            end
+            res = res .. spaces .. string.rep(" ", indent or 0)
+            res = res .. json.dumps(val, indent, sortKeys, depth + 1)
+        end
+        res = res .. ifNil(indent, "", "\n") .. spaces .. "]"
+    elseif t == "table" then
+        res = res .. "{" .. ifNil(indent, "", "\n")
+        local first = true
+        local keys = {}
+        for k, _ in pairs(data) do
+            table.insert(keys, k)
+        end
+        if sortKeys then
+            table.sort(keys)
+        end
+        for _, k in ipairs(keys) do
+            local v = data[k]
+            if not first then
+                res = res .. "," .. ifNil(indent, " ", "\n")
+            end
+            first = false
+            res = res .. spaces .. string.rep(" ", indent or 0)
+            res = res .. '"' .. escapeStr(k) .. '": '
+            res = res .. json.dumps(v, indent, sortKeys, depth + 1)
+        end
+        res = res .. ifNil(indent, "", "\n") .. spaces .. "}"
+    end
+
+    return res
+end
+
 return json

src/lib/progress.lua

@@ -0,0 +1,14 @@
+local utils = require("utils")
+local progress = {}
+
+function progress.bar(x, y, width, value, max, fg, bg)
+    local fgWidth = utils.round(value * width / max)
+    fgWidth = math.max(0, math.min(width, fgWidth))
+    paintutils.drawLine(x, y, x + width - 1, y, bg)
+    if fgWidth > 0 then
+        paintutils.drawLine(x, y, x + fgWidth - 1, y, fg)
+    end
+    term.setBackgroundColor(colors.black)
+end
+
+return progress

src/lib/utils.lua

@@ -1,7 +1,7 @@
 local utils = {}
 
-function utils.promptChoices(choices)
+function utils.promptChoices(choices, default)
-    local c = 1
+    local c = default or 1
     local ox, oy = term.getCursorPos()
     while true do
         term.setCursorPos(ox, oy)
@@ -11,7 +11,11 @@ function utils.promptChoices(choices)
             else
                 term.setTextColor(colors.lightGray)
             end
-            print(choice)
+            local label = choice
+            if type(choice) == "table" then
+                label = choice[1] or choice["label"]
+            end
+            print(label)
         end
         local event, key, is_held = os.pullEvent("key")
         if key == keys.up then
@@ -23,7 +27,11 @@ function utils.promptChoices(choices)
         end
     end
     term.setTextColor(colors.white)
-    return choices[c]
+    local choice = choices[c]
+    if type(choice) == "table" then
+        choice = choice[2] or choice["value"]
+    end
+    return choice
 end
 
 function utils.readFile(path)
@@ -70,4 +78,20 @@ function utils.waitForKey(targetKey)
     end
 end
 
+function utils.split(data, sep)
+    local t = {}
+    for str in string.gmatch(data, "([^" .. sep .. "]+)") do
+        table.insert(t, str)
+    end
+    return t
+end
+
+function utils.splitLines(data)
+    return utils.split(data, "\n")
+end
+
+function utils.round(x)
+    return x >= 0 and math.floor(x + 0.5) or math.ceil(x - 0.5)
+end
+
 return utils