diff --git a/2021/day24/main.go b/2021/day24/main.go
index a63e1d3..0752c6e 100644
--- a/2021/day24/main.go
+++ b/2021/day24/main.go
@@ -1,220 +1,54 @@
 package main
 
 import (
-	"bufio"
 	"fmt"
-	"math"
-	"os"
-	"strconv"
 	"strings"
 
 	h "git.bullercodeworks.com/brian/adventofcode/helpers"
 )
 
 func main() {
-	fmt.Println("ALU")
-	if len(os.Args) < 2 {
-		fmt.Println("Must pass filename as argument")
-		os.Exit(1)
-	}
-	test(os.Args[1])
-	//part1(os.Args[1])
+	inp := h.StdinToStringSlice()
+	solve(1, inp)
+	fmt.Println("")
+	solve(2, inp)
 }
 
-func test(fn string) {
-	fmt.Println("# Test")
-	num := "15"
-	alu := NewALU()
-	alu.ReadProgram(fn)
-	var done bool
-	for !done {
-		fmt.Println("Converting", num)
-		alu.BufferInput(strings.Split(num, ""))
-		alu.run()
-		if num == "0" {
-			done = true
-		}
-		num = decNum(num, len(num)-1)
-	}
+type pair struct {
+	first  int
+	second int
 }
 
-func decNum(num string, idx int) string {
-	if idx < 0 {
-		return num
-	}
-	if len(num) < idx {
-		return num
-	}
-	if num[idx] == '0' && idx > 0 {
-		num = num[:idx] + "9" + num[idx+1:]
-		return decNum(num, idx-1)
-	}
-	num = num[:idx] + string(num[idx]-1) + num[idx+1:]
-	return num
-}
-
-func part1(fn string) {
-	fmt.Println("# Part 1")
-	var done bool
-	num := "99999999999999"
-	alu := NewALU()
-	alu.ReadProgram(fn)
-	for !done {
-		fmt.Println("Checking Model No.", num)
-		alu.BufferInput(strings.Split(num, ""))
-		alu.run()
-		if alu.registers["z"] == 0 {
-			fmt.Println("-> It's good.")
-			done = true
-		}
-		num = decModelNum(num, len(num)-1)
-	}
-}
-
-func decModelNum(num string, idx int) string {
-	if len(num) < idx {
-		return num
-	}
-	if num[idx] == '1' {
-		num = num[:idx] + "9" + num[idx+1:]
-		return decModelNum(num, idx-1)
-	}
-	num = num[:idx] + string(num[idx]-1) + num[idx+1:]
-	return num
-}
-
-const (
-	INPUT_MODE_USER = iota
-	INPUT_MODE_CHAN
-)
-
-type ALU struct {
-	program   []string
-	registers map[string]int
-	ptr       int
-	inputMode int
-	inputChan chan string
-}
-
-func NewALU() *ALU {
-	return &ALU{
-		registers: map[string]int{"w": 0, "x": 0, "y": 0, "z": 0},
-		ptr:       0,
-		inputChan: make(chan string, 14),
-	}
-}
-
-func (alu *ALU) BufferInput(inp []string) {
-	alu.inputMode = INPUT_MODE_CHAN
-	for i := range inp {
-		alu.inputChan <- inp[i]
-	}
-}
-
-func (alu *ALU) ReadProgram(fn string) error {
-	file, err := os.Open(fn)
-	if err != nil {
-		return err
-	}
-	defer file.Close()
-
-	var lines []string
-	scanner := bufio.NewScanner(file)
-	for scanner.Scan() {
-		lines = append(lines, scanner.Text())
-	}
-	alu.program = lines
-	return scanner.Err()
-}
-
-func (alu *ALU) printRegisters() {
-	fmt.Printf("Registers:\nw: %d\nx: %d\ny: %d\nz: %d\n", alu.registers["w"], alu.registers["x"], alu.registers["y"], alu.registers["z"])
-}
-
-func (alu *ALU) run() {
-	for alu.ptr = 0; alu.ptr < len(alu.program); alu.ptr++ {
-		pts := strings.Split(alu.program[alu.ptr], " ")
-		switch pts[0] {
-		case "inp":
-			alu.registers[pts[1]] = alu.inp()
-		case "add":
-			alu.registers[pts[1]] = alu.add(alu.value(pts[1]), alu.value(pts[2]))
-		case "mul":
-			alu.registers[pts[1]] = alu.mul(alu.value(pts[1]), alu.value(pts[2]))
-		case "div":
-			alu.registers[pts[1]] = alu.div(alu.value(pts[1]), alu.value(pts[2]))
-		case "mod":
-			alu.registers[pts[1]] = alu.mod(alu.value(pts[1]), alu.value(pts[2]))
-		case "eql":
-			alu.registers[pts[1]] = alu.eql(alu.value(pts[1]), alu.value(pts[2]))
-		}
-	}
-}
-
-func (alu *ALU) inp() int {
-	if alu.inputMode == INPUT_MODE_USER {
-		var inp string
-		var err error
-		var v int
-		for inp == "" || err != nil {
-			fmt.Println("Input value:")
-			reader := bufio.NewReader(os.Stdin)
-			inp, _ = reader.ReadString('\n')
-			inp = strings.TrimSpace(inp)
-			v, err = strconv.Atoi(inp)
-			if err != nil {
-				fmt.Println("Must be an integer.")
+func solve(part int, inp []string) {
+	var model [14]int
+	var stack []pair
+	for i := 0; i < 14; i++ {
+		xAdd := h.Atoi(strings.Fields(inp[18*i+5])[2])
+		yAdd := h.Atoi(strings.Fields(inp[18*i+15])[2])
+		if xAdd > 0 {
+			stack = append(stack, pair{first: yAdd, second: i})
+		} else {
+			var s pair
+			var toAdd int
+			s, stack = stack[len(stack)-1], stack[:len(stack)-1]
+			if part == 1 {
+				toAdd = 9
+				for toAdd+s.first+xAdd > 9 {
+					toAdd--
+				}
+			} else if part == 2 {
+				toAdd = 1
+				for toAdd+s.first+xAdd < 1 {
+					toAdd++
+				}
 			}
-		}
-		return v
-	} else if alu.inputMode == INPUT_MODE_CHAN {
-		v, err := strconv.Atoi(<-alu.inputChan)
-		if err == nil {
-			return v
+			model[s.second] = toAdd
+			model[i] = toAdd + s.first + xAdd
 		}
 	}
-	return 0
-}
-
-func (alu *ALU) value(a string) int {
-	switch a {
-	case "w", "x", "y", "z":
-		return alu.registers[a]
-	default:
-		return h.Atoi(a)
+	fmt.Println("# Part", part)
+	for i := range model {
+		fmt.Print(model[i])
 	}
-}
-
-func (alu *ALU) add(a, b int) int {
-	return a + b
-}
-
-func (alu *ALU) mul(a, b int) int {
-	return a * b
-}
-
-func (alu *ALU) div(a, b int) int {
-	if b == 0 {
-		return 0
-	}
-	aD, bD := float64(a), float64(b)
-	d := aD / bD
-	if d > 0 {
-		return int(math.Floor(d))
-	}
-	return int(math.Ceil(d))
-}
-
-func (alu *ALU) mod(a, b int) int {
-	if a < 0 || b <= 0 {
-		return 0
-	}
-	return a % b
-}
-
-func (alu *ALU) eql(a, b int) int {
-	if a == b {
-		return 1
-	}
-	return 0
+	fmt.Println()
 }
diff --git a/2021/day24/parts.csv b/2021/day24/parts.csv
new file mode 100644
index 0000000..88220e5
--- /dev/null
+++ b/2021/day24/parts.csv
@@ -0,0 +1,18 @@
+inp w,inp w,inp w,inp w,inp w,inp w,inp w,inp w,inp w,inp w,inp w,inp w,inp w,inp w
+mul x 0,mul x 0,mul x 0,mul x 0,mul x 0,mul x 0,mul x 0,mul x 0,mul x 0,mul x 0,mul x 0,mul x 0,mul x 0,mul x 0
+add x z,add x z,add x z,add x z,add x z,add x z,add x z,add x z,add x z,add x z,add x z,add x z,add x z,add x z
+mod x 26,mod x 26,mod x 26,mod x 26,mod x 26,mod x 26,mod x 26,mod x 26,mod x 26,mod x 26,mod x 26,mod x 26,mod x 26,mod x 26
+div z 1,div z 1,div z 1,div z 26,div z 1,div z 26,div z 1,div z 1,div z 1,div z 26,div z 26,div z 26,div z 26,div z 26
+add x 10,add x 13,add x 13,add x -11,add x 11,add x -4,add x 12,add x 12,add x 15,add x -2,add x -5,add x -11,add x -13,add x -10
+eql x w,eql x w,eql x w,eql x w,eql x w,eql x w,eql x w,eql x w,eql x w,eql x w,eql x w,eql x w,eql x w,eql x w
+eql x 0,eql x 0,eql x 0,eql x 0,eql x 0,eql x 0,eql x 0,eql x 0,eql x 0,eql x 0,eql x 0,eql x 0,eql x 0,eql x 0
+mul y 0,mul y 0,mul y 0,mul y 0,mul y 0,mul y 0,mul y 0,mul y 0,mul y 0,mul y 0,mul y 0,mul y 0,mul y 0,mul y 0
+add y 25,add y 25,add y 25,add y 25,add y 25,add y 25,add y 25,add y 25,add y 25,add y 25,add y 25,add y 25,add y 25,add y 25
+mul y x,mul y x,mul y x,mul y x,mul y x,mul y x,mul y x,mul y x,mul y x,mul y x,mul y x,mul y x,mul y x,mul y x
+add y 1,add y 1,add y 1,add y 1,add y 1,add y 1,add y 1,add y 1,add y 1,add y 1,add y 1,add y 1,add y 1,add y 1
+mul z y,mul z y,mul z y,mul z y,mul z y,mul z y,mul z y,mul z y,mul z y,mul z y,mul z y,mul z y,mul z y,mul z y
+mul y 0,mul y 0,mul y 0,mul y 0,mul y 0,mul y 0,mul y 0,mul y 0,mul y 0,mul y 0,mul y 0,mul y 0,mul y 0,mul y 0
+add y w,add y w,add y w,add y w,add y w,add y w,add y w,add y w,add y w,add y w,add y w,add y w,add y w,add y w
+add y 13,add y 10,add y 3,add y 1,add y 9,add y 3,add y 5,add y 1,add y 0,add y 13,add y 7,add y 15,add y 12,add y 8
+mul y x,mul y x,mul y x,mul y x,mul y x,mul y x,mul y x,mul y x,mul y x,mul y x,mul y x,mul y x,mul y x,mul y x
+add z y,add z y,add z y,add z y,add z y,add z y,add z y,add z y,add z y,add z y,add z y,add z y,add z y,add z y