2019 Day 24 Complete

2019/day24/layout.go

@@ -0,0 +1,112 @@
+package main
+
+import (
+	"log"
+	"math"
+	"strings"
+
+	"io/ioutil"
+
+	h "git.bullercodeworks.com/brian/adventofcode/helpers"
+)
+
+type Layout struct {
+	Area        map[h.Coordinate]bool
+	BottomRight h.Coordinate
+
+	History map[string]float64
+}
+
+func NewLayout(filename string) *Layout {
+	ret := Layout{
+		Area:        make(map[h.Coordinate]bool),
+		BottomRight: h.Coordinate{X: 0, Y: 0},
+		History:     make(map[string]float64),
+	}
+	input, err := ioutil.ReadFile(filename)
+	if err != nil {
+		log.Fatal(err.Error())
+	}
+	lines := make([]string, 0)
+	for _, line := range strings.Split(string(input), "\n") {
+		lines = append(lines, line)
+	}
+	for y := 0; y < len(lines); y++ {
+		if len(lines[y]) < ret.BottomRight.X {
+			break
+		}
+		ret.BottomRight.Y = y
+		for x := 0; x < len(lines[y]); x++ {
+			ret.BottomRight.X = x
+			ret.Area[h.Coordinate{X: x, Y: y}] = lines[y][x] == '#'
+		}
+	}
+	ret.SaveToHistory()
+	return &ret
+}
+
+func (l Layout) SaveToHistory() {
+	l.History[l.String()] = l.Rating()
+}
+
+func (l Layout) Rating() float64 {
+	var rating, pow float64
+	for y := 0; y <= l.BottomRight.Y; y++ {
+		for x := 0; x <= l.BottomRight.X; x++ {
+			if l.Area[h.Coordinate{X: x, Y: y}] {
+				rating = rating + math.Pow(2, pow)
+			}
+			pow++
+		}
+	}
+	return rating
+}
+
+func (l Layout) Step() bool {
+	a := make(map[h.Coordinate]bool)
+	for k, v := range l.Area {
+		a[k] = v
+	}
+	for y := 0; y <= l.BottomRight.Y; y++ {
+		for x := 0; x <= l.BottomRight.X; x++ {
+			c := h.Coordinate{X: x, Y: y}
+			neighbors := 0
+			for _, v := range []h.Coordinate{c.North(), c.East(), c.South(), c.West()} {
+				if n, ok := l.Area[v]; ok && n {
+					neighbors++
+				}
+			}
+			if l.Area[c] {
+				if neighbors != 1 {
+					a[c] = false
+				}
+			} else {
+				if neighbors == 1 || neighbors == 2 {
+					a[c] = true
+				}
+			}
+		}
+	}
+	for k, v := range a {
+		l.Area[k] = v
+	}
+	// Finally check/save to history
+	_, ok := l.History[l.String()]
+	l.History[l.String()] = l.Rating()
+	return ok
+}
+
+func (l Layout) String() string {
+	var ret string
+	for y := 0; y <= l.BottomRight.Y; y++ {
+		for x := 0; x <= l.BottomRight.X; x++ {
+			if l.Area[h.Coordinate{X: x, Y: y}] {
+				ret = ret + "#"
+			} else {
+				ret = ret + "."
+			}
+		}
+		ret = ret + "\n"
+	}
+	return ret
+}