aoc2023/day10/maze.go
2023-12-12 21:58:03 +01:00

117 lines
2.6 KiB
Go

package main
import (
"bufio"
"fmt"
"log"
"os"
"sync"
"time"
)
// Parallel code, global vars
type Maze struct {
mu sync.Mutex
direction [][]rune
steps int
}
var mapDirections = map[rune]int8{
'|': 0, // Vertical
'-': 1, // Horizontal
'L': 2, // North to East
'J': 3, // North to West
'7': 4, // South to West
'F': 5, // South to East
'.': 6, // Ground
'S': 7, // Start
}
func check(e error) {
if e != nil {
panic(e)
}
}
func PrintAndWait(x ...any) {
fmt.Print(x...)
fmt.Scanln()
}
// use defer timer("funcname")() when the function you want to
// test starts
func timer(name string) func() {
start := time.Now()
return func() {
fmt.Printf("%s took %v\n", name, time.Since(start))
}
}
func (mz *Maze) ChooseFirstDirection(startPoint [2]int) [2]int {
// For the first step, we don't care about directions, we only need a tile
// were we can step on. E.g., if we have a J North of S we CAN'T go. A 7 would
// be OK.
x := startPoint[0]
y := startPoint[1]
// If x - 1 (going west), only 1, 2, 5 allowed
temp := mapDirections[mz.direction[x-1][y]]
if temp == 1 || temp == 2 || temp == 5 {
PrintAndWait("We go West boi")
// If x + 1 (going east), only 1, 3, 4 allowed
} else if temp := mapDirections[mz.direction[x+1][y]]; temp == 1 || temp == 3 || temp == 4 {
PrintAndWait("We go East boi")
// If y - 1 (going north), only 0, 4, 5 allowed
} else if temp := mapDirections[mz.direction[x][y-1]]; temp == 0 || temp == 4 || temp == 5 {
PrintAndWait("We go North boi")
} else {
log.Fatal("How is this even possible..?")
}
}
func (mz *Maze) FindPath(startPoint [2]int) {
nextCheck := startPoint
nextCheck = mz.ChooseFirstDirection(nextCheck)
}
func main() {
if len(os.Args) != 2 {
fmt.Println("Must provide exactly one argument. It must be a file.")
log.Fatal("NOW I WILL SCREAM AND DIE.")
}
file, err := os.Open(os.Args[1])
check(err)
defer file.Close()
lines := make([]string, 0)
mz := Maze{}
scanner := bufio.NewScanner(file)
for scanner.Scan() {
lines = append(lines, scanner.Text())
}
numColumns := len(lines)
mz.direction = make([][]rune, numColumns)
// Populate the array of directions
for i := 0; i < numColumns; i++ {
for j := 0; j < len(lines[i]); j++ {
mz.direction[i] = append(mz.direction[i], rune(lines[i][j]))
}
}
var startPoint [2]int
// Search for the starting point
for i := 0; i < numColumns; i++ {
for j := 0; j < len(lines[i]); j++ {
if mapDirections[mz.direction[i][j]] == 7 {
startPoint[0] = i
startPoint[1] = j
}
}
}
// Going west: x - 1 | Going east: x + 1
// Going north: y - 1 | Going south: y + 1
mz.FindPath(startPoint)
}