adventofcode/2022/day22/main.go

423 lines
8.0 KiB
Go

package main
import (
"fmt"
"math"
h "git.bullercodeworks.com/brian/adventofcode/helpers"
)
func main() {
inp := h.StdinToStringSlice()
//part1(inp)
part2(inp)
}
func part1(inp []string) {
board, inst := inp[:len(inp)-2], inp[len(inp)-1]
b := BuildBoard(board)
var count int
var turn byte
fmt.Println(b)
fmt.Println(b.pos)
for len(inst) > 0 {
count, turn, inst = getNextInstructions(inst)
b.Move(count)
if turn == 'L' || turn == 'R' {
b.Turn(turn)
}
}
fmt.Println("Password:", b.Password())
}
func part2(inp []string) {
board, inst := inp[:len(inp)-2], inp[len(inp)-1]
b := BuildCubeBoard(board)
var count int
var turn byte
fmt.Println(b)
fmt.Println(b.pos)
for len(inst) > 0 {
count, turn, inst = getNextInstructions(inst)
b.Move(count)
if turn == 'L' || turn == 'R' {
b.Turn(turn)
}
}
fmt.Println("Password:", b.Password())
}
func getNextInstructions(inst string) (int, byte, string) {
for i := range inst {
if inst[i] == 'L' || inst[i] == 'R' {
return h.Atoi(inst[:i]), inst[i], inst[i+1:]
}
}
return h.Atoi(inst), 0, ""
}
const (
dirR = iota
dirD
dirL
dirU
dirErr
sideTop = iota
sideBottom
sideRight
sideLeft
sideFront
sideBack
)
type CubeBoard struct {
Top *CubeBoardSide
Bottom *CubeBoardSide
Left *CubeBoardSide
Right *CubeBoardSide
Front *CubeBoardSide
Back *CubeBoardSide
// Pos now holds:
// y, x, dir, side
pos []int
}
// For the purposes of directions, we treat the board like this:
// [T]
// [B][L][F][R]
// [B]
// So up from left, front, back, and right are all top
// Up from bottom is front
// Down from bottom is back
// Up from top is back
// Down from top is front
// So you can continually go left on the main level and circumnavigate the cube
// Continually going up from anywhere will eventually get you bouncing between top and back
// Continually going down from anywhere will eventually get you bouncing between bottom and back
func BuildCubeBoard(inp []string) *CubeBoard {
cb := CubeBoard{}
var side string
for i := 0; i < len(inp); i++ {
if len(inp) == 0 {
break
}
side = inp[i]
i++
cbs := BuildCubeBoardSide(inp[i : i+len(inp[i])])
switch side {
case "Top":
cb.Top = cbs
case "Bottom":
cb.Bottom = cbs
case "Left":
cb.Left = cbs
case "Right":
cb.Right = cbs
case "Front":
cb.Front = cbs
case "Back":
cb.Back = cbs
}
i = i + cbs.Size() - 1
}
cb.pos = []int{0, 0, dirR, sideTop}
return &cb
}
func (cb *CubeBoard) Size() int { return cb.Top.Size() }
func (cb *CubeBoard) Move(count int) {
}
func (cb *CubeBoard) GetPosUp() []int {
y := cb.pos[0]
x := cb.pos[1]
dir := cb.pos[2]
side := cb.pos[3]
if y == 0 {
// Going to another side
switch side {
case sideTop:
side = sideBack
case sideBottom:
side = sideFront
case sideFront:
side = sideTop
case sideBack:
side = sideTop
case sideLeft:
side = sideTop
case sideRight:
side = sideTop
}
}
return []int{y, x, dir, side}
}
func (cb *CubeBoard) GetPosDown() []int {
y := cb.pos[0]
x := cb.pos[1]
dir := cb.pos[2]
side := cb.pos[3]
if y == cb.Size()-1 {
// Going to another side
switch side {
case sideTop:
side = sideFront
case sideBottom:
side = sideBack
case sideFront:
side = sideBottom
case sideBack:
side = sideBottom
case sideLeft:
side = sideBottom
case sideRight:
side = sideBottom
}
} else {
y = y + 1
}
return []int{y, x, dir, side}
}
func (cb *CubeBoard) GetPosRight() []int {
y := cb.pos[0]
x := cb.pos[1]
dir := cb.pos[2]
side := cb.pos[3]
if x == cb.Size()-1 {
// Going to another side
switch side {
case sideTop:
side = sideRight
case sideBottom:
side = sideRight
case sideFront:
side = sideRight
case sideBack:
side = sideLeft
case sideLeft:
side = sideFront
case sideRight:
side = sideBack
}
} else {
y = y + 1
}
return []int{y, x, dir, side}
}
// Get the current pos' side
func (cb *CubeBoard) Side() *CubeBoardSide {
switch cb.pos[3] {
case sideTop:
return cb.Top
case sideBottom:
return cb.Bottom
case sideFront:
return cb.Front
case sideBack:
return cb.Back
case sideLeft:
return cb.Left
case sideRight:
return cb.Right
}
return nil
}
func (cb *CubeBoard) Turn(dir byte) {
if dir == 'R' {
cb.pos[2] = (cb.pos[2] + 1) % dirErr
} else if dir == 'L' {
cb.pos[2] = (cb.pos[2] - 1 + dirErr) % dirErr
}
}
func (cb *CubeBoard) Tile(y, x, side int) byte {
switch side {
case sideTop:
return cb.Top.Tile(y, x)
case sideBottom:
return cb.Bottom.Tile(y, x)
case sideLeft:
return cb.Left.Tile(y, x)
case sideRight:
return cb.Right.Tile(y, x)
case sideFront:
return cb.Front.Tile(y, x)
case sideBack:
return cb.Back.Tile(y, x)
}
return 0
}
func (cb *CubeBoard) Password() int {
return 0
}
type CubeBoardSide struct {
spots [][]byte
}
func BuildCubeBoardSide(inp []string) *CubeBoardSide {
cbs := CubeBoardSide{}
fmt.Println("Building CBS from:", inp)
cbs.spots = make([][]byte, len(inp))
for y := range inp {
row := make([]byte, len(inp[y]))
for x := range inp[y] {
row[x] = inp[y][x]
}
cbs.spots[y] = row
}
return &cbs
}
func (cbs *CubeBoardSide) Size() int {
return len(cbs.spots)
}
func (cbs *CubeBoardSide) Tile(y, x int) byte {
if len(cbs.spots) < y && len(cbs.spots[y]) < x {
return cbs.spots[y][x]
}
return 0
}
type Board struct {
spots [][]byte
// pos holds
// y, x, dir
pos []int
}
func BuildBoard(inp []string) *Board {
maxX := math.MinInt
for y := range inp {
maxX = h.Max(maxX, len(inp[y]))
}
b := Board{
spots: make([][]byte, len(inp)),
}
for y := range inp {
sl := make([]byte, maxX)
for x := range inp[y] {
sl[x] = inp[y][x]
}
b.spots[y] = sl
}
b.pos = make([]int, 3)
for x := range b.spots[0] {
if b.spots[0][x] == '.' {
b.pos = []int{0, x, dirR}
break
}
}
return &b
}
func (b *Board) Password() int {
return ((b.pos[0] + 1) * 1000) + ((b.pos[1] + 1) * 4) + b.pos[2]
}
func (b *Board) Tile(y, x int) byte {
if len(b.spots) > y && len(b.spots[y]) > x {
return b.spots[y][x]
}
return 0
}
func (b *Board) GetNextPos() []int {
switch b.pos[2] {
case dirU:
return b.GetPosUp()
case dirR:
return b.GetPosRight()
case dirD:
return b.GetPosDown()
case dirL:
return b.GetPosLeft()
}
return []int{-1, -1}
}
func (b *Board) GetPosUp() []int {
x := b.pos[1]
y := ((b.pos[0] - 1) + len(b.spots)) % len(b.spots)
for (b.spots[y][x] == 0 || b.spots[y][x] == 32) && y != b.pos[0] {
y = ((y - 1) + len(b.spots)) % len(b.spots)
}
return []int{y, x}
}
func (b *Board) GetPosRight() []int {
y := b.pos[0]
x := (b.pos[1] + 1) % len(b.spots[y])
for (b.spots[y][x] == 0 || b.spots[y][x] == 32) && x != b.pos[1] {
x = (x + 1) % len(b.spots[y])
}
return []int{y, x}
}
func (b *Board) GetPosDown() []int {
x := b.pos[1]
y := (b.pos[0] + 1) % len(b.spots)
for (b.spots[y][x] == 0 || b.spots[y][x] == 32) && y != b.pos[0] {
y = (y + 1) % len(b.spots)
}
return []int{y, x}
}
func (b *Board) GetPosLeft() []int {
y := b.pos[0]
x := ((b.pos[1] - 1) + len(b.spots[y])) % len(b.spots[y])
for (b.spots[y][x] == 0 || b.spots[y][x] == 32) && x != b.pos[1] {
x = ((x - 1) + len(b.spots[y])) % len(b.spots[y])
}
return []int{y, x}
}
func (b *Board) Move(count int) {
var to []int
for count > 0 {
switch b.pos[2] {
case dirU:
to = b.GetPosUp()
case dirR:
to = b.GetPosRight()
case dirD:
to = b.GetPosDown()
case dirL:
to = b.GetPosLeft()
}
if b.Tile(to[0], to[1]) == '.' {
count--
b.pos[0], b.pos[1] = to[0], to[1]
} else {
break
}
}
}
func (b *Board) Turn(dir byte) {
if dir == 'R' {
b.pos[2] = (b.pos[2] + 1) % dirErr
} else if dir == 'L' {
b.pos[2] = (b.pos[2] - 1 + dirErr) % dirErr
}
}
func (b Board) String() string {
var ret string
for y := range b.spots {
for x := range b.spots[y] {
bt := b.spots[y][x]
if b.pos[1] == x && b.pos[0] == y {
switch b.pos[2] {
case dirU:
bt = '^'
case dirR:
bt = '>'
case dirD:
bt = 'v'
case dirL:
bt = '<'
default:
bt = '!'
}
}
ret = ret + fmt.Sprint(string(bt))
}
ret = ret + "\n"
}
return ret
}