Working d8p1

This commit is contained in:
Davide Oddone 2023-12-09 23:00:54 +01:00
parent 574fdf38a4
commit a17153662e
2 changed files with 85 additions and 40 deletions

1
.gitignore vendored
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@ -22,3 +22,4 @@ go.work
# Problem data
input*.txt
inputs/

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@ -1,23 +1,23 @@
package main
import(
"fmt"
import (
"bufio"
"fmt"
"os"
"sync"
"regexp"
"context"
"sync"
)
const LEFT = 'L'
type Nodes struct {
mu sync.Mutex
commands []int32
singleN []int32
leftN []int32
rightN []int32
steps uint64
mu sync.Mutex
commands []int32
singleN []int32
leftN []int32
rightN []int32
index int
steps uint64
}
func check(e error) {
@ -32,64 +32,108 @@ func PrintAndWait(x ...any) {
}
func (n *Nodes) toByteSingle(s string) {
// I've just received something like AAA
var temp int32
for i := 0; i < len(s); i++ {
a := int32(s[i])
temp += a << (i*8)
}
// I've just received something like AAA
var temp int32
for i := len(s) - 1; i >= 0; i-- {
a := int32(s[i])
temp += a << ((len(s) - 1 - i) * 8)
}
n.singleN = append(n.singleN, temp)
}
func (n *Nodes) toByteDuet(s, r string) {
// I've just received something like AAA BBB
var tempL, tempR int32
for i := 0; i < len(s); i++ {
tempL += int32(s[i]) << (i*8)
tempR += int32(s[i]) << (i*8)
}
n.leftN = append(n.leftN, tempL)
n.rightN = append(n.rightN, tempR)
// I've just received something like AAA BBB
var tempL, tempR int32
for i := len(s) - 1; i >= 0; i-- {
tempL += int32(s[i]) << ((len(s) - 1 - i) * 8)
tempR += int32(r[i]) << ((len(s) - 1 - i) * 8)
//fmt.Printf("Received %c (%b), now I have %b | ", s[i], s[i], tempL)
//fmt.Printf("Received %c (%b), now I have %b\n", r[i], r[i], tempR)
//fmt.Scanln()
}
n.leftN = append(n.leftN, tempL)
n.rightN = append(n.rightN, tempR)
}
func (n *Nodes) findNext(direction int32, index int, ctx context.Context) {
func (n *Nodes) findNext(myN int32) {
//var wg sync.WaitGroup
for i := 0; i < len(n.singleN); i++ {
if myN^n.singleN[i] == 0 {
n.index = i
break
}
}
}
func main() {
file, err := os.Open("./inputs/day08_test_input")
file, err := os.Open("./inputs/day08_input")
check(err)
defer file.Close()
// Struct with my node
n := Nodes{}
// Prepare the regex
repath := regexp.MustCompile("([A-Z]{3})")
// Build the END
var END = 'Z'
END += ('Z' << 8)
END += ('Z' << 16)
scanner := bufio.NewScanner(file)
scanner.Scan()
// First line, RL commands
strCommands := scanner.Text()
// Get every char inside the string just obtained
for i := 0; i < len(strCommands); i++ {
n.commands = append(n.commands, int32(strCommands[i]))
n.commands = append(n.commands, int32(strCommands[i]))
}
// One empty line
scanner.Scan()
// X = (Y, Z)
// We regex this one
for scanner.Scan() {
tempNodes := repath.FindAllString(scanner.Text(), -1)
n.toByteSingle(tempNodes[0])
n.toByteDuet(tempNodes[1], tempNodes[2])
tempNodes := repath.FindAllString(scanner.Text(), -1)
n.toByteSingle(tempNodes[0])
n.toByteDuet(tempNodes[1], tempNodes[2])
}
ctx, cancel := context.WithCancel(context.Background())
defer cancel()
// We start from 0, we find the match
for i, j := 0, 0; ; i++ {
// We do a circular loop
i = i % len(n.commands)
// A function that has the context as an argument
n.findNext(int32(i), j, ctx)
j++
// Let's start an infinite loop
// Circular index
i := 0
// We start from the AAA element
START := 'A'
START += ('A' << 8)
START += ('A' << 16)
matching := START
// Store where AAA is
n.findNext(matching)
// By default, we will assume we are on the right
// If we are not, we are in the left
matching = n.rightN[n.index]
if n.commands[i]^LEFT == 0 {
matching = n.leftN[n.index]
}
n.steps++
// Infinite loop
for {
// Every step is in a single direction. For every step, we may need to
// scan len(n.singleN) elements.
// Circular loop
n.findNext(matching)
// Increment i after finding the match
i++
i = i % len(n.commands)
// By default, we will assume we are on the right
matching = n.rightN[n.index]
//PrintAndWait()
// If we are not, we are in the left
if n.commands[i]^LEFT == 0 {
matching = n.leftN[n.index]
}
n.steps++
// If we find ZZZ, end
if matching^END == 0 {
break
}
}
fmt.Printf("\nSteps: %d\n", n.steps)
}