From 616713e8ae8a83e114fba6d52af8a5770e2ca3a8 Mon Sep 17 00:00:00 2001
From: Luke Else <mail@luke-else.co.uk>
Date: Sun, 12 Dec 2021 00:23:08 +0000
Subject: [PATCH] day 11b complete

fairly simple after finally figuring out where I went wrong in part A.

Note - Struct included in solution inspired by online solution
---
 day11/day 11b/go.mod    |   3 +
 day11/day 11b/main.go   | 149 ++++++++++++++++++++++++++++++++++++++++
 day11/day 11b/testInput |  10 +++
 3 files changed, 162 insertions(+)
 create mode 100644 day11/day 11b/go.mod
 create mode 100644 day11/day 11b/main.go
 create mode 100644 day11/day 11b/testInput

diff --git a/day11/day 11b/go.mod b/day11/day 11b/go.mod
new file mode 100644
index 0000000..e938e2e
--- /dev/null
+++ b/day11/day 11b/go.mod	
@@ -0,0 +1,3 @@
+module PWD
+
+go 1.17
diff --git a/day11/day 11b/main.go b/day11/day 11b/main.go
new file mode 100644
index 0000000..8abd24d
--- /dev/null
+++ b/day11/day 11b/main.go	
@@ -0,0 +1,149 @@
+package main
+
+import (
+	"bufio"
+	"fmt"
+	"os"
+	"strconv"
+)
+
+func main() {
+	content := returnContent("../input")
+	//content := returnContent("testInput")
+
+	octopuses := map[Coordinate]int{}
+
+	answer := 0
+
+	width := 0
+	height := len(*content)
+
+	//Insert octopuses into a map
+	for y, row := range *content {
+		width = len(row)
+		for x, val := range row {
+			octopuses[Coordinate{X: x, Y: y}] = val
+		}
+	}
+
+	i := 0
+	for {
+		i++
+		flashers := map[Coordinate]bool{}
+		for coords, energy := range octopuses {
+			octopuses[coords] = energy + 1
+		}
+
+		for {
+			doneFlashing := true
+
+			for coords, energy := range octopuses {
+				if energy > 9 && !flashers[coords] {
+					doneFlashing = false
+					flashers[coords] = true
+					for _, neighbour := range coords.Neighbours(width, height, true) {
+						octopuses[neighbour]++
+					}
+				}
+			}
+
+			if doneFlashing {
+				break
+			}
+		}
+
+		for coords, flashed := range flashers {
+			if flashed {
+				octopuses[coords] = 0
+			}
+		}
+
+		allFlashed := true
+		for y := 0; y < height; y++ {
+			for x := 0; x < width; x++ {
+				if !flashers[Coordinate{
+					X: x,
+					Y: y,
+				}] {
+					allFlashed = false
+				}
+			}
+		}
+		if allFlashed {
+			answer = i
+			break
+		}
+	}
+
+	//fmt.Println(*content)
+	fmt.Println(answer)
+}
+
+//Coordinate Class
+type Coordinate struct {
+	X int
+	Y int
+}
+
+func (c *Coordinate) Neighbours(gridWidth int, gridHeight int, diagonal bool) (out []Coordinate) {
+	spaceLeft := c.X > 0
+	spaceRight := c.X < gridWidth-1
+	spaceUp := c.Y > 0
+	spaceDown := c.Y < gridHeight-1
+
+	if spaceLeft {
+		out = append(out, Coordinate{c.X - 1, c.Y})
+	}
+	if spaceRight {
+		out = append(out, Coordinate{c.X + 1, c.Y})
+	}
+	if spaceUp {
+		out = append(out, Coordinate{c.X, c.Y - 1})
+	}
+	if spaceDown {
+		out = append(out, Coordinate{c.X, c.Y + 1})
+	}
+
+	if diagonal {
+		if spaceUp && spaceLeft {
+			out = append(out, Coordinate{c.X - 1, c.Y - 1})
+		}
+		if spaceUp && spaceRight {
+			out = append(out, Coordinate{c.X + 1, c.Y - 1})
+		}
+		if spaceDown && spaceLeft {
+			out = append(out, Coordinate{c.X - 1, c.Y + 1})
+		}
+		if spaceDown && spaceRight {
+			out = append(out, Coordinate{c.X + 1, c.Y + 1})
+		}
+	}
+
+	return
+}
+
+func returnContent(path string) *[][]int {
+	//read file and return it as an array of integers
+
+	file, err := os.Open(path)
+	var content [][]int
+
+	if err != nil {
+		fmt.Println("Unlucky, the file didn't open")
+		return &content
+	}
+	defer file.Close()
+
+	scanner := bufio.NewScanner(file)
+
+	for scanner.Scan() {
+		nums := []int{}
+		for _, char := range scanner.Text() {
+			num, _ := strconv.Atoi(string(char))
+			nums = append(nums, num)
+		}
+		content = append(content, nums)
+	}
+
+	return &content
+}
diff --git a/day11/day 11b/testInput b/day11/day 11b/testInput
new file mode 100644
index 0000000..a3819c9
--- /dev/null
+++ b/day11/day 11b/testInput	
@@ -0,0 +1,10 @@
+5483143223
+2745854711
+5264556173
+6141336146
+6357385478
+4167524645
+2176841721
+6882881134
+4846848554
+5283751526
\ No newline at end of file