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 # Problem data
input*.txt input*.txt
inputs/

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@ -1,12 +1,11 @@
package main package main
import( import (
"fmt"
"bufio" "bufio"
"fmt"
"os" "os"
"sync"
"regexp" "regexp"
"context" "sync"
) )
const LEFT = 'L' const LEFT = 'L'
@ -17,6 +16,7 @@ type Nodes struct {
singleN []int32 singleN []int32
leftN []int32 leftN []int32
rightN []int32 rightN []int32
index int
steps uint64 steps uint64
} }
@ -34,9 +34,9 @@ func PrintAndWait(x ...any) {
func (n *Nodes) toByteSingle(s string) { func (n *Nodes) toByteSingle(s string) {
// I've just received something like AAA // I've just received something like AAA
var temp int32 var temp int32
for i := 0; i < len(s); i++ { for i := len(s) - 1; i >= 0; i-- {
a := int32(s[i]) a := int32(s[i])
temp += a << (i*8) temp += a << ((len(s) - 1 - i) * 8)
} }
n.singleN = append(n.singleN, temp) n.singleN = append(n.singleN, temp)
} }
@ -44,26 +44,39 @@ func (n *Nodes) toByteSingle(s string) {
func (n *Nodes) toByteDuet(s, r string) { func (n *Nodes) toByteDuet(s, r string) {
// I've just received something like AAA BBB // I've just received something like AAA BBB
var tempL, tempR int32 var tempL, tempR int32
for i := 0; i < len(s); i++ { for i := len(s) - 1; i >= 0; i-- {
tempL += int32(s[i]) << (i*8) tempL += int32(s[i]) << ((len(s) - 1 - i) * 8)
tempR += int32(s[i]) << (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.leftN = append(n.leftN, tempL)
n.rightN = append(n.rightN, tempR) 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() { func main() {
file, err := os.Open("./inputs/day08_test_input") file, err := os.Open("./inputs/day08_input")
check(err) check(err)
defer file.Close() defer file.Close()
// Struct with my node // Struct with my node
n := Nodes{} n := Nodes{}
// Prepare the regex // Prepare the regex
repath := regexp.MustCompile("([A-Z]{3})") repath := regexp.MustCompile("([A-Z]{3})")
// Build the END
var END = 'Z'
END += ('Z' << 8)
END += ('Z' << 16)
scanner := bufio.NewScanner(file) scanner := bufio.NewScanner(file)
scanner.Scan() scanner.Scan()
@ -82,14 +95,45 @@ func main() {
n.toByteSingle(tempNodes[0]) n.toByteSingle(tempNodes[0])
n.toByteDuet(tempNodes[1], tempNodes[2]) n.toByteDuet(tempNodes[1], tempNodes[2])
} }
ctx, cancel := context.WithCancel(context.Background())
defer cancel()
// We start from 0, we find the match // We start from 0, we find the match
for i, j := 0, 0; ; i++ { // Let's start an infinite loop
// We do a circular loop // Circular index
i = i % len(n.commands) i := 0
// A function that has the context as an argument // We start from the AAA element
n.findNext(int32(i), j, ctx) START := 'A'
j++ 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)
} }