Advent Of Code, day 5

day5.go

package aoc18

import (
	"io/ioutil"
	"log"
	"strconv"
	"strings"
)

type Maze struct {
	offsets    []int
	steps      int
	currentIdx int
}

func (m *Maze) Jump(increase func()) {
	val := m.offsets[m.currentIdx]
	increase()
	m.currentIdx += val
	m.steps++
}

func (m *Maze) CanEscape() bool {
	return m.currentIdx > len(m.offsets)-1
}

func (m *Maze) Solve(increase func()) int {
	for {
		if m.CanEscape() {
			return m.steps
		}
		m.Jump(increase)
	}
}

func SolveFirstPart(fileName string) int {
	input := string(OpenFile(fileName))
	offsets := adaptInput(input)
	maze := Maze{offsets, 0, 0}
	return maze.Solve(func() {
		maze.offsets[maze.currentIdx]++
	})
}

func SolveSecondPart(fileName string) int {
	input := string(OpenFile(fileName))
	maze := Maze{adaptInput(input), 0, 0}
	return maze.Solve(func() {
		val := maze.offsets[maze.currentIdx]
		if val >= 3 {
			maze.offsets[maze.currentIdx]--
		} else {
			maze.offsets[maze.currentIdx]++
		}

	})
}

func adaptInput(input string) []int {
	input = strings.Replace(input, "\r", "", -1)
	arr := strings.Split(input, "\n")
	offsets := []int{}
	for _, val := range arr {
		intVal, _ := strconv.Atoi(val)
		offsets = append(offsets, intVal)
	}
	return offsets
}

func OpenFile(fileName string) []byte {
	file, err := ioutil.ReadFile(fileName)
	if err != nil {
		log.Fatal(err)
	}
	return file
}