From a83808326691ec80e79dd5c5ed53b66532aceb6a Mon Sep 17 00:00:00 2001
From: Karl Spickermann <karliosos65@googlemail.com>
Date: Sat, 11 Dec 2021 17:40:29 +0100
Subject: [PATCH] Day11

---
 src/day11/day11.go          | 96 +++++++++++++++++++++++++++++++++++++
 src/day11/day11Input.txt    | 10 ++++
 src/day11/day11StepTest.txt |  5 ++
 src/day11/day11Test.txt     | 10 ++++
 4 files changed, 121 insertions(+)
 create mode 100644 src/day11/day11.go
 create mode 100644 src/day11/day11Input.txt
 create mode 100644 src/day11/day11StepTest.txt
 create mode 100644 src/day11/day11Test.txt

diff --git a/src/day11/day11.go b/src/day11/day11.go
new file mode 100644
index 0000000..b0a0172
--- /dev/null
+++ b/src/day11/day11.go
@@ -0,0 +1,96 @@
+package main
+
+import (
+	"AOC2021/src/helper"
+	"fmt"
+	"os"
+)
+
+type field struct {
+	energy  int
+	flashed bool
+}
+
+func main() {
+	args := os.Args[1:]
+	input, err := helper.GetInput(args[0])
+	if err != nil {
+		fmt.Println(err)
+	}
+	energyMap := [10][10]field{}
+	for i, line := range input {
+		for j, r := range line {
+			energyMap[i][j] = field{int(r - '0'), false}
+		}
+	}
+	flashes := 0
+	allFlashTogether := false
+	i := 0
+	for !allFlashTogether {
+		stepflashes := step(&energyMap)
+		flashes += stepflashes
+		if stepflashes == 100 {
+			fmt.Printf("First Step, where all octuspuses flash simultaneously: %d \n", i + 1)
+			allFlashTogether = true
+		}
+		if i == 99 {
+			fmt.Printf("Flashes after 100 Steps: %d \n", flashes)
+		}
+		i++
+	}
+}
+
+func step(energyMap *[10][10]field) int{
+	flashes := 0
+	for i, _ := range energyMap {
+		for j, _ := range energyMap[i] {
+			energyMap[i][j].energy++
+		}
+	}
+	for i, _ := range energyMap {
+		for j, _ := range energyMap[i] {
+			if energyMap[i][j].energy > 9 {
+				flash(energyMap, j, i)
+			}
+		}
+	}
+	for i, _ := range energyMap {
+		for j, _ := range energyMap[i] {
+			if energyMap[i][j].flashed {
+				energyMap[i][j].energy = 0
+				flashes++
+				energyMap[i][j].flashed = false
+			}
+		}
+	}
+	return flashes
+}
+
+func flash(energyMap *[10][10]field, x int, y int) {
+	if energyMap[y][x].flashed == true {
+		return
+	}
+	energyMap[y][x].flashed = true
+	directions := [8][2]int{{-1, -1}, {0, -1}, {1, -1}, {+1, 0}, {1, 1}, {0, 1}, {-1, 1}, {-1, 0}}
+	for _, direction := range directions {
+		px := x + direction[0]
+		py := y + direction[1]
+		if py < len(energyMap) && py >= 0 && px < len(energyMap[0]) && px >= 0 {
+			energyMap[py][px].energy++
+			if energyMap[py][px].energy > 9 {
+				flash(energyMap, px, py)
+			}
+		}
+	}
+}
+
+func printMap(energyMap *[10][10]field)  {
+	for _, line := range energyMap {
+		lineArray := [10]int{}
+		for i, field := range line {
+			lineArray[i] = field.energy
+		}
+		fmt.Println(lineArray)
+	}
+
+}
diff --git a/src/day11/day11Input.txt b/src/day11/day11Input.txt
new file mode 100644
index 0000000..dfa8b6e
--- /dev/null
+++ b/src/day11/day11Input.txt
@@ -0,0 +1,10 @@
+2138862165
+2726378448
+3235172758
+6281242643
+4256223158
+1112268142
+1162836182
+1543525861
+1882656326
+8844263151
\ No newline at end of file
diff --git a/src/day11/day11StepTest.txt b/src/day11/day11StepTest.txt
new file mode 100644
index 0000000..e282ad7
--- /dev/null
+++ b/src/day11/day11StepTest.txt
@@ -0,0 +1,5 @@
+11111
+19991
+19191
+19991
+11111
\ No newline at end of file
diff --git a/src/day11/day11Test.txt b/src/day11/day11Test.txt
new file mode 100644
index 0000000..a3819c9
--- /dev/null
+++ b/src/day11/day11Test.txt
@@ -0,0 +1,10 @@
+5483143223
+2745854711
+5264556173
+6141336146
+6357385478
+4167524645
+2176841721
+6882881134
+4846848554
+5283751526
\ No newline at end of file