From 6cbca15c3d87afba4b9c3d57fe4ca9707dc33770 Mon Sep 17 00:00:00 2001
From: Karl Spickermann <karlhspickermann@gmail.de>
Date: Thu, 22 Dec 2022 03:14:11 +0100
Subject: [PATCH] Day21

---
 day21/day21.go | 93 +++++++++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 92 insertions(+), 1 deletion(-)

diff --git a/day21/day21.go b/day21/day21.go
index 4693ef3..da0fdb2 100644
--- a/day21/day21.go
+++ b/day21/day21.go
@@ -3,6 +3,7 @@ package main
 import (
 	"AOC2022/helper"
 	"fmt"
+	"math"
 	"strconv"
 	"strings"
 )
@@ -17,6 +18,97 @@ type Operation struct {
 func main() {
 	//args := os.Args[1:]
 	lines := helper.ReadTextFile("day21/input")
+	//part1(lines)
+	fmt.Println(part2(lines))
+	fmt.Println(testNumber(lines, 3403989691757))
+
+}
+
+func part2(lines []string) int {
+	currentBestDifference := 99999999999999
+	currentI := 0
+	for currentBestDifference > 0 {
+		startingDifference := testNumber(lines, currentI)
+		fmt.Println(startingDifference)
+		increaseDifference := testNumber(lines, currentI+1)
+		reduceDifference := testNumber(lines, currentI-1)
+		if increaseDifference < reduceDifference {
+			fmt.Println("Up we go")
+			currentI, currentBestDifference = checkForward(lines, currentBestDifference, currentI)
+		} else {
+			fmt.Println("Down we go")
+			currentI, currentBestDifference = checkBackward(lines, currentBestDifference, currentI)
+		}
+	}
+	fmt.Println(currentI)
+	return 0
+}
+
+func checkForward(lines []string, increaseDifference int, startI int) (int, int) {
+	i := startI
+	increaser := 1000000000
+	for increaser > 0 {
+		differenceDoesntDecreaseAnymore := false
+		for !differenceDoesntDecreaseAnymore {
+			i += increaser
+			tmpDifference := testNumber(lines, i)
+			if tmpDifference < increaseDifference {
+				increaseDifference = tmpDifference
+			} else {
+				i -= increaser
+				differenceDoesntDecreaseAnymore = true
+			}
+		}
+		increaser /= 10
+	}
+	return i, increaseDifference
+}
+
+func checkBackward(lines []string, increaseDifference int, startI int) (int, int) {
+	i := startI
+	increaser := 1000000000
+	for increaser > 0 {
+		differenceDoesntDecreaseAnymore := false
+		for !differenceDoesntDecreaseAnymore {
+			i -= increaser
+			tmpDifference := testNumber(lines, i)
+			if tmpDifference < increaseDifference {
+				increaseDifference = tmpDifference
+			} else {
+				i += increaser
+				differenceDoesntDecreaseAnymore = true
+			}
+		}
+		increaser /= 10
+	}
+	return i, increaseDifference
+}
+
+func testNumber(lines []string, testnumber int) int {
+	apes := make(map[string]Operation)
+	apesWithValue := []string{}
+	apesWithOutValue := []string{}
+	for _, line := range lines {
+		id, operation := getApe(line)
+		apes[id] = operation
+		if len(operation.operator) > 0 {
+			apesWithOutValue = append(apesWithOutValue, id)
+		} else {
+			apesWithValue = append(apesWithValue, id)
+		}
+	}
+	humnApe := apes["humn"]
+	humnApe.value = testnumber
+	apes["humn"] = humnApe
+	for len(apesWithOutValue) > 1 {
+		apesWithOutValue = step(apesWithOutValue, &apes)
+	}
+	rootApe1Val := apes[apes["root"].apes[0]].value
+	rootApe2Val := apes[apes["root"].apes[1]].value
+	return int(math.Abs(float64(rootApe1Val - rootApe2Val)))
+}
+
+func part1(lines []string) {
 	apes := make(map[string]Operation)
 	apesWithValue := []string{}
 	apesWithOutValue := []string{}
@@ -35,7 +127,6 @@ func main() {
 		apesWithOutValue = step(apesWithOutValue, &apes)
 	}
 	fmt.Print(apes["root"])
-
 }
 
 func step(apesWithOutValue []string, apes *map[string]Operation) []string {