2025: day6: JS

AdventOfCode2025/day3/bin/dune

@@ -0,0 +1,3 @@
+(executable
+ (public_name day3)
+ (name main))

AdventOfCode2025/day3/bin/main.ml

@@ -0,0 +1,86 @@
+let get_highest_number_and_index l =
+    let (t, _) = List.fold_left (
+        fun ((highest, highest_index), index) i -> 
+            if i > highest then 
+                ((i, index), index + 1) 
+        else 
+            ((highest, highest_index), index + 1)
+    ) ((0, 0), 0) (List.rev l) in
+    t
+
+let rec first_n k xs = match xs with
+| [] -> failwith "firstk"
+| x::xs -> if k=1 then [x] else x::first_n (k-1) xs
+
+let slice_at_index l index =
+    let rec loop (i, acc) =
+        match acc with
+        | [] -> failwith "too far"
+        | _ :: tail -> if i == index then tail else loop (i + 1, tail)
+    in
+    loop (0, List.rev l)
+
+let highest_n n l =
+    let rec loop acc n l =
+        match n with
+        | 0 -> acc
+        | n -> 
+            let list_first_n_items = first_n (List.length l - n + 1) (List.rev l) |> List.rev  in
+            let (highest, highest_index) = get_highest_number_and_index list_first_n_items in
+            let remaining_list = slice_at_index l highest_index in
+            loop (highest :: acc) (n - 1) (List.rev remaining_list)
+        in
+    loop [] n l
+            
+let string_to_int_list l =
+    l 
+    |> String.to_seq  
+    |> List.of_seq 
+    |> List.fold_left (fun acc i -> ((int_of_char i) - (int_of_char '0')) :: acc) []
+
+let num_from_int_list l =
+    let rec loop acc index l =
+        match l with
+        | [] -> acc
+        | head :: tail -> loop (acc + index * head) (index * 10) tail
+    in
+    loop 0 1 l
+            
+
+
+let solve lines =
+    let nums_part1 = List.fold_left (
+        fun acc line -> (line |> string_to_int_list |> (highest_n 2)) :: acc
+    ) [] lines in
+
+    let part1 = List.fold_left (+) 0 (List.map num_from_int_list nums_part1) in
+
+    let nums_part2 = List.fold_left (
+        fun acc line -> (line |> string_to_int_list |> (highest_n 12)) :: acc
+    ) [] lines in
+
+    let part2 = List.fold_left (+) 0 (List.map num_from_int_list nums_part2) in
+
+    (part1, part2)
+
+let read_lines name =
+  let ic = open_in name in
+  let try_read () = try Some (input_line ic) with End_of_file -> None in
+  let rec loop acc =
+    match try_read () with
+    | Some s -> loop (s :: acc)
+    | None ->
+        close_in ic;
+        List.rev acc
+  in
+  loop []
+
+let () =
+print_endline "Day 3";
+  let part1, part2 =
+    read_lines "./input.txt" |> solve
+  in
+  Printf.printf "Part 1: %s\nPart 2: %s\n" (string_of_int part1)
+    (string_of_int part2)
+
+

AdventOfCode2025/day3/day3.opam

@@ -0,0 +1,32 @@
+# This file is generated by dune, edit dune-project instead
+opam-version: "2.0"
+synopsis: "A short synopsis"
+description: "A longer description"
+maintainer: ["Maintainer Name <maintainer@example.com>"]
+authors: ["Author Name <author@example.com>"]
+license: "LICENSE"
+tags: ["add topics" "to describe" "your" "project"]
+homepage: "https://github.com/username/reponame"
+doc: "https://url/to/documentation"
+bug-reports: "https://github.com/username/reponame/issues"
+depends: [
+  "dune" {>= "3.20"}
+  "ocaml"
+  "odoc" {with-doc}
+]
+build: [
+  ["dune" "subst"] {dev}
+  [
+    "dune"
+    "build"
+    "-p"
+    name
+    "-j"
+    jobs
+    "@install"
+    "@runtest" {with-test}
+    "@doc" {with-doc}
+  ]
+]
+dev-repo: "git+https://github.com/username/reponame.git"
+x-maintenance-intent: ["(latest)"]

AdventOfCode2025/day3/dune-project

@@ -0,0 +1,26 @@
+(lang dune 3.20)
+
+(name day3)
+
+(generate_opam_files true)
+
+(source
+ (github username/reponame))
+
+(authors "Author Name <author@example.com>")
+
+(maintainers "Maintainer Name <maintainer@example.com>")
+
+(license LICENSE)
+
+(documentation https://url/to/documentation)
+
+(package
+ (name day3)
+ (synopsis "A short synopsis")
+ (description "A longer description")
+ (depends ocaml)
+ (tags
+  ("add topics" "to describe" your project)))
+
+; See the complete stanza docs at https://dune.readthedocs.io/en/stable/reference/dune-project/index.html

AdventOfCode2025/day4/.gitignore

@@ -0,0 +1,34 @@
+# dependencies (bun install)
+node_modules
+
+# output
+out
+dist
+*.tgz
+
+# code coverage
+coverage
+*.lcov
+
+# logs
+logs
+_.log
+report.[0-9]_.[0-9]_.[0-9]_.[0-9]_.json
+
+# dotenv environment variable files
+.env
+.env.development.local
+.env.test.local
+.env.production.local
+.env.local
+
+# caches
+.eslintcache
+.cache
+*.tsbuildinfo
+
+# IntelliJ based IDEs
+.idea
+
+# Finder (MacOS) folder config
+.DS_Store

AdventOfCode2025/day4/README.md

@@ -0,0 +1,15 @@
+# day4
+
+To install dependencies:
+
+```bash
+bun install
+```
+
+To run:
+
+```bash
+bun run index.ts
+```
+
+This project was created using `bun init` in bun v1.2.8. [Bun](https://bun.sh) is a fast all-in-one JavaScript runtime.

AdventOfCode2025/day4/bun.lock

@@ -0,0 +1,25 @@
+{
+  "lockfileVersion": 1,
+  "workspaces": {
+    "": {
+      "name": "day4",
+      "devDependencies": {
+        "@types/bun": "latest",
+      },
+      "peerDependencies": {
+        "typescript": "^5",
+      },
+    },
+  },
+  "packages": {
+    "@types/bun": ["@types/bun@1.3.3", "", { "dependencies": { "bun-types": "1.3.3" } }, "sha512-ogrKbJ2X5N0kWLLFKeytG0eHDleBYtngtlbu9cyBKFtNL3cnpDZkNdQj8flVf6WTZUX5ulI9AY1oa7ljhSrp+g=="],
+
+    "@types/node": ["@types/node@24.10.1", "", { "dependencies": { "undici-types": "~7.16.0" } }, "sha512-GNWcUTRBgIRJD5zj+Tq0fKOJ5XZajIiBroOF0yvj2bSU1WvNdYS/dn9UxwsujGW4JX06dnHyjV2y9rRaybH0iQ=="],
+
+    "bun-types": ["bun-types@1.3.3", "", { "dependencies": { "@types/node": "*" } }, "sha512-z3Xwlg7j2l9JY27x5Qn3Wlyos8YAp0kKRlrePAOjgjMGS5IG6E7Jnlx736vH9UVI4wUICwwhC9anYL++XeOgTQ=="],
+
+    "typescript": ["typescript@5.9.3", "", { "bin": { "tsc": "bin/tsc", "tsserver": "bin/tsserver" } }, "sha512-jl1vZzPDinLr9eUt3J/t7V6FgNEw9QjvBPdysz9KfQDD41fQrC2Y4vKQdiaUpFT4bXlb1RHhLpp8wtm6M5TgSw=="],
+
+    "undici-types": ["undici-types@7.16.0", "", {}, "sha512-Zz+aZWSj8LE6zoxD+xrjh4VfkIG8Ya6LvYkZqtUQGJPZjYl53ypCaUwWqo7eI0x66KBGeRo+mlBEkMSeSZ38Nw=="],
+  }
+}

AdventOfCode2025/day4/index.ts

@@ -0,0 +1,78 @@
+const file = Bun.file("./input.txt");
+const content = await file.text();
+
+const EMPTY = ".";
+const PAPER = "@";
+
+const splitContent = [...content.trim().split("\n")]
+const lineSize = splitContent[0]!.length
+
+const grid = [
+    '.'.repeat(lineSize),
+    ...splitContent,
+    '.'.repeat(lineSize),
+].map(l => `.${l}.`.split(""))
+
+const solve = (grid: string[][]): [number, string[][]] => {
+    let paperRemoved = 0;
+    const newGrid = structuredClone(grid)
+
+    for (let y = 1; y < grid.length - 1; y++) {
+        for (let x = 1; x < grid[0]!.length - 1; x++) {
+            let adjacentPapers = 0;
+
+            const currentSquare = grid?.[y]?.[x]
+            if (!currentSquare) {
+                throw new Error("current square must be defined")
+            }
+
+            if (currentSquare === EMPTY) {
+                continue
+            }
+
+            for (let yOffset = -1; yOffset <= 1; yOffset++) {
+                for (let xOffset = -1; xOffset <= 1; xOffset++) {
+                    if (yOffset === 0 && xOffset === 0) {
+                        continue
+                    }
+
+                    const square = grid![y + yOffset]![x + xOffset]!
+                    if (square === PAPER) {
+                        adjacentPapers++
+                    }
+                }
+            }
+
+            if (adjacentPapers < 4) {
+                newGrid![y]![x] = EMPTY
+                paperRemoved++
+            }
+        }
+    }
+
+    return [paperRemoved, newGrid]
+}
+
+const removePaper = (grid: string[][]): number => {
+    let totalPaperRemoved = 0;
+    let currentGrid = grid
+
+    while (true) {
+        const [paperRemoved, newGrid] = solve(currentGrid)
+        currentGrid = newGrid
+
+        if (paperRemoved === 0) {
+            break
+        }
+
+        totalPaperRemoved += paperRemoved
+    }
+
+    return totalPaperRemoved
+}
+
+const [part1] = solve(grid)
+const part2 = removePaper(grid)
+
+console.log("Part 1: ", part1)
+console.log("Part 2: ", part2)

AdventOfCode2025/day4/package.json

@@ -0,0 +1,12 @@
+{
+  "name": "day4",
+  "module": "index.ts",
+  "type": "module",
+  "private": true,
+  "devDependencies": {
+    "@types/bun": "latest"
+  },
+  "peerDependencies": {
+    "typescript": "^5"
+  }
+}

AdventOfCode2025/day4/tsconfig.json

@@ -0,0 +1,28 @@
+{
+  "compilerOptions": {
+    // Environment setup & latest features
+    "lib": ["ESNext"],
+    "target": "ESNext",
+    "module": "ESNext",
+    "moduleDetection": "force",
+    "jsx": "react-jsx",
+    "allowJs": true,
+
+    // Bundler mode
+    "moduleResolution": "bundler",
+    "allowImportingTsExtensions": true,
+    "verbatimModuleSyntax": true,
+    "noEmit": true,
+
+    // Best practices
+    "strict": true,
+    "skipLibCheck": true,
+    "noFallthroughCasesInSwitch": true,
+    "noUncheckedIndexedAccess": true,
+
+    // Some stricter flags (disabled by default)
+    "noUnusedLocals": false,
+    "noUnusedParameters": false,
+    "noPropertyAccessFromIndexSignature": false
+  }
+}

AdventOfCode2025/day5/bin/dune

@@ -0,0 +1,4 @@
+(executable
+ (public_name day5)
+ (name main)
+ (libraries day5))

AdventOfCode2025/day5/bin/main.ml

@@ -0,0 +1,144 @@
+let get_range str =
+    let list = (String.split_on_char '-' str) 
+        |> List.map int_of_string in
+
+    assert (List.length list == 2);
+    
+    let lower = List.nth list 0 in
+    let upper = List.nth list 1 in
+
+    (lower, upper)
+
+let is_item_in_range  i (lower, upper) = 
+    lower <= i && i <= upper
+
+let rec list_some l fn = 
+    match l with 
+    | [] -> false
+    | head :: tail -> if fn head then true else list_some tail fn
+
+let is_item_in_ranges ranges i =
+    list_some ranges (is_item_in_range i)
+
+
+let is_overlapping (lower1, upper1) (lower2, upper2) =
+    lower1 <= lower2 && lower2 <= upper1 ||
+    lower2 <= lower1 && lower1 <= upper2
+
+let get_combined_ranges (lower1, upper1) (lower2, upper2) =
+    let lower = min lower1 lower2 in
+    let upper = max upper1 upper2 in
+    (lower, upper)
+
+let non_overlapping_ranges_work ranges =
+    let rec loop acc changes ranges =
+        match ranges with 
+        | [] -> (acc, changes)
+        | head :: tail -> 
+            let overlap_fn = is_overlapping head in
+            let overlapping_index = List.find_index overlap_fn tail in
+            match overlapping_index with
+            | Some r -> 
+                let (l, u) = List.nth tail r in
+                let tail_without_index = List.filter 
+                    (fun (lower, upper) -> not (lower == l && upper == u)) tail in
+                let combined_range = get_combined_ranges head (l, u) in
+                loop (combined_range :: acc) true (tail_without_index)
+            | None -> loop (head :: acc) changes tail
+    in
+    loop [] false ranges
+
+(* let rec print_ranges l = *)
+(*     match l with  *)
+(*     | [] -> print_endline ""; *)
+(*     | (lower, upper) :: tail ->  *)
+(*         Printf.printf "lower=%d,upper=%d\n" lower upper; *)
+(*         print_ranges tail *)
+        
+
+let rec non_overlapping_ranges ranges =
+    let (ranges, changes)  = non_overlapping_ranges_work ranges in
+    if changes then non_overlapping_ranges ranges
+    else ranges
+
+    
+let solve lines = 
+    let no_empty_lines = List.filter (fun i -> String.length i > 0) lines in
+    let (ranges, items) = List.partition (fun i -> String.contains i '-') no_empty_lines in
+
+    let ranges = List.map get_range ranges in
+    let items = List.map int_of_string items in
+
+    let part1 = List.fold_left (
+        fun acc i -> if is_item_in_ranges ranges i then acc + 1 else acc
+    ) 0 items in
+
+    let ranges = non_overlapping_ranges ranges in
+     
+    let part2 = List.fold_left (
+        fun acc (lower, upper) -> acc + (upper - lower + 1)
+    ) 0 ranges in
+
+    (part1, part2)
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+let read_lines name =
+  let ic = open_in name in
+  let try_read () = try Some (input_line ic) with End_of_file -> None in
+  let rec loop acc =
+    match try_read () with
+    | Some s -> loop (s :: acc)
+    | None ->
+        close_in ic;
+        List.rev acc
+  in
+  loop []
+
+let () =
+print_endline "Day 5";
+  let part1, part2 =
+    read_lines "./input.txt" |> solve
+  in
+  Printf.printf "Part 1: %s\nPart 2: %s\n" (string_of_int part1)
+    (string_of_int part2)
+
+

AdventOfCode2025/day5/day5.opam

@@ -0,0 +1,32 @@
+# This file is generated by dune, edit dune-project instead
+opam-version: "2.0"
+synopsis: "A short synopsis"
+description: "A longer description"
+maintainer: ["Maintainer Name <maintainer@example.com>"]
+authors: ["Author Name <author@example.com>"]
+license: "LICENSE"
+tags: ["add topics" "to describe" "your" "project"]
+homepage: "https://github.com/username/reponame"
+doc: "https://url/to/documentation"
+bug-reports: "https://github.com/username/reponame/issues"
+depends: [
+  "dune" {>= "3.20"}
+  "ocaml"
+  "odoc" {with-doc}
+]
+build: [
+  ["dune" "subst"] {dev}
+  [
+    "dune"
+    "build"
+    "-p"
+    name
+    "-j"
+    jobs
+    "@install"
+    "@runtest" {with-test}
+    "@doc" {with-doc}
+  ]
+]
+dev-repo: "git+https://github.com/username/reponame.git"
+x-maintenance-intent: ["(latest)"]

AdventOfCode2025/day5/dune-project

@@ -0,0 +1,26 @@
+(lang dune 3.20)
+
+(name day5)
+
+(generate_opam_files true)
+
+(source
+ (github username/reponame))
+
+(authors "Author Name <author@example.com>")
+
+(maintainers "Maintainer Name <maintainer@example.com>")
+
+(license LICENSE)
+
+(documentation https://url/to/documentation)
+
+(package
+ (name day5)
+ (synopsis "A short synopsis")
+ (description "A longer description")
+ (depends ocaml)
+ (tags
+  ("add topics" "to describe" your project)))
+
+; See the complete stanza docs at https://dune.readthedocs.io/en/stable/reference/dune-project/index.html

AdventOfCode2025/day5/lib/dune

@@ -0,0 +1,2 @@
+(library
+ (name day5))

AdventOfCode2025/day5/test/dune

@@ -0,0 +1,2 @@
+(test
+ (name test_day5))

AdventOfCode2025/day6/.gitignore

@@ -0,0 +1,34 @@
+# dependencies (bun install)
+node_modules
+
+# output
+out
+dist
+*.tgz
+
+# code coverage
+coverage
+*.lcov
+
+# logs
+logs
+_.log
+report.[0-9]_.[0-9]_.[0-9]_.[0-9]_.json
+
+# dotenv environment variable files
+.env
+.env.development.local
+.env.test.local
+.env.production.local
+.env.local
+
+# caches
+.eslintcache
+.cache
+*.tsbuildinfo
+
+# IntelliJ based IDEs
+.idea
+
+# Finder (MacOS) folder config
+.DS_Store

AdventOfCode2025/day6/README.md

@@ -0,0 +1,15 @@
+# day6
+
+To install dependencies:
+
+```bash
+bun install
+```
+
+To run:
+
+```bash
+bun run index.ts
+```
+
+This project was created using `bun init` in bun v1.2.8. [Bun](https://bun.sh) is a fast all-in-one JavaScript runtime.

AdventOfCode2025/day6/bun.lock

@@ -0,0 +1,25 @@
+{
+  "lockfileVersion": 1,
+  "workspaces": {
+    "": {
+      "name": "day6",
+      "devDependencies": {
+        "@types/bun": "latest",
+      },
+      "peerDependencies": {
+        "typescript": "^5",
+      },
+    },
+  },
+  "packages": {
+    "@types/bun": ["@types/bun@1.3.3", "", { "dependencies": { "bun-types": "1.3.3" } }, "sha512-ogrKbJ2X5N0kWLLFKeytG0eHDleBYtngtlbu9cyBKFtNL3cnpDZkNdQj8flVf6WTZUX5ulI9AY1oa7ljhSrp+g=="],
+
+    "@types/node": ["@types/node@24.10.1", "", { "dependencies": { "undici-types": "~7.16.0" } }, "sha512-GNWcUTRBgIRJD5zj+Tq0fKOJ5XZajIiBroOF0yvj2bSU1WvNdYS/dn9UxwsujGW4JX06dnHyjV2y9rRaybH0iQ=="],
+
+    "bun-types": ["bun-types@1.3.3", "", { "dependencies": { "@types/node": "*" } }, "sha512-z3Xwlg7j2l9JY27x5Qn3Wlyos8YAp0kKRlrePAOjgjMGS5IG6E7Jnlx736vH9UVI4wUICwwhC9anYL++XeOgTQ=="],
+
+    "typescript": ["typescript@5.9.3", "", { "bin": { "tsc": "bin/tsc", "tsserver": "bin/tsserver" } }, "sha512-jl1vZzPDinLr9eUt3J/t7V6FgNEw9QjvBPdysz9KfQDD41fQrC2Y4vKQdiaUpFT4bXlb1RHhLpp8wtm6M5TgSw=="],
+
+    "undici-types": ["undici-types@7.16.0", "", {}, "sha512-Zz+aZWSj8LE6zoxD+xrjh4VfkIG8Ya6LvYkZqtUQGJPZjYl53ypCaUwWqo7eI0x66KBGeRo+mlBEkMSeSZ38Nw=="],
+  }
+}

AdventOfCode2025/day6/index.ts

@@ -0,0 +1,116 @@
+const file = Bun.file("./input.txt");
+const content = await file.text().then((c) => c.trim());
+
+const filterNonEmpty = (i: string) => i.length > 0
+
+type Problem = {
+    operation: string
+    numbers: number[]
+}
+
+const problems: Problem[] = [];
+
+const splitContent = content.split("\n")
+const operationsRow = splitContent.pop()!.split(" ").filter(filterNonEmpty)
+
+for (const line of splitContent) {
+    const numbers = line.split(" ").filter(filterNonEmpty);
+    if (problems.length === 0) {
+        for (let i = 0; i < numbers.length; i++) {
+            problems.push({
+                operation: '',
+                numbers: [],
+            })
+        }
+    }
+
+    for (let i = 0; i < numbers.length; i++) {
+        problems[i]!.numbers.push(parseInt(numbers[i]!))
+    }
+}
+
+for (const [index, problem] of problems.entries()) {
+    problem.operation = operationsRow[index]!
+}
+
+const getReducer = (op: string): (nums: number[]) => number => {
+    switch (op) {
+        case '*':
+            return (nums) => nums.reduce((n, acc) => acc * n, 1)
+        case '+':
+            return (nums) => nums.reduce((n, acc) => acc + n, 0)
+        default:
+            throw new Error("operation not supported")
+    }
+}
+
+const solve = (problems: Problem[]): number => {
+    let part1 = 0;
+
+    for (const problem of problems) {
+        const reducer = getReducer(problem.operation)
+        part1 += reducer(problem.numbers)
+    }
+
+    return part1
+}
+
+const transposeProblems = (str: string): Problem[] => {
+    const charArr = str.split("\n").map(c => c.split(""))
+
+    const newCharArr: string[][] = [];
+
+    for (let i = 0; i < charArr.length; i++) {
+        for (let j = 0; j < charArr[0]!.length; j++) {
+            if (!newCharArr[j]) {
+                newCharArr[j] = []
+            }
+            newCharArr[j]![i]! = charArr[i]![j]! ?? ' '
+        }
+    }
+
+    const problems: Problem[] = [];
+    let workingProblem: Problem = {
+        numbers: [],
+        operation: ""
+    }
+    let index = 0;
+
+    for (const line of newCharArr) {
+        if (line.every(c => c === " ")) {
+            problems.push(workingProblem)
+            workingProblem = {
+                numbers: [],
+                operation: ''
+            }
+            index = 0
+            continue
+        }
+
+        if (index === 0) {
+            const op = line.pop()
+            if (op !== " ") {
+                workingProblem.operation = op!
+            }
+        }
+
+        const numbers = line.filter(c => c !== " ")
+        if (numbers.length === 0) {
+            continue
+        }
+
+        const number = parseInt(numbers.join(""))
+        workingProblem.numbers.push(number)
+    }
+
+    problems.push(workingProblem)
+
+    return problems
+}
+
+const part1 = solve(problems)
+console.log("Part 1: ", part1)
+
+const part2Problems = transposeProblems(content)
+const part2 = solve(part2Problems)
+console.log("Part 2: ", part2)

AdventOfCode2025/day6/package.json

@@ -0,0 +1,12 @@
+{
+  "name": "day6",
+  "module": "index.ts",
+  "type": "module",
+  "private": true,
+  "devDependencies": {
+    "@types/bun": "latest"
+  },
+  "peerDependencies": {
+    "typescript": "^5"
+  }
+}

AdventOfCode2025/day6/tsconfig.json

@@ -0,0 +1,28 @@
+{
+  "compilerOptions": {
+    // Environment setup & latest features
+    "lib": ["ESNext"],
+    "target": "ESNext",
+    "module": "ESNext",
+    "moduleDetection": "force",
+    "jsx": "react-jsx",
+    "allowJs": true,
+
+    // Bundler mode
+    "moduleResolution": "bundler",
+    "allowImportingTsExtensions": true,
+    "verbatimModuleSyntax": true,
+    "noEmit": true,
+
+    // Best practices
+    "strict": true,
+    "skipLibCheck": true,
+    "noFallthroughCasesInSwitch": true,
+    "noUncheckedIndexedAccess": true,
+
+    // Some stricter flags (disabled by default)
+    "noUnusedLocals": false,
+    "noUnusedParameters": false,
+    "noPropertyAccessFromIndexSignature": false
+  }
+}