[ADD] main: Added day 9 solution

09/main.go

@@ -0,0 +1,186 @@
+package main
+
+import (
+	"bufio"
+	"fmt"
+	"os"
+	"slices"
+	"time"
+)
+
+const FILE_PATH = "./input.txt"
+
+//const FILE_PATH = "./sample.txt"
+
+func LoadInput(filename string) ([]string, error) {
+	file, err := os.Open(filename)
+	if err != nil {
+		return nil, err
+	}
+	defer file.Close()
+
+	var lines []string
+	scanner := bufio.NewScanner(file)
+	for scanner.Scan() {
+		lines = append(lines, scanner.Text())
+	}
+
+	if err := scanner.Err(); err != nil {
+		return nil, err
+	}
+
+	return lines, nil
+}
+
+type structuredInput = string
+
+func TransformInput(lines []string) structuredInput {
+	return lines[0]
+}
+
+type Block struct {
+	id     int
+	length int
+	free   int
+
+	used     int
+	freeUsed int
+}
+
+func Part1CreateBlocks(input structuredInput) []Block {
+	var result = make([]Block, 0)
+	var temp Block
+	for i := 0; i < len(input); i += 2 {
+		temp = Block{id: i / 2, length: int(input[i] - '0')}
+		if i+1 < len(input) {
+			temp.free = int(input[i+1] - '0')
+		}
+		result = append(result, temp)
+	}
+
+	return result
+}
+
+func Part1(input structuredInput) int {
+	var result = 0
+
+	var blocks = Part1CreateBlocks(input)
+	var j = 0
+
+	for i := 0; i < len(blocks); i++ {
+		for blocks[i].used != blocks[i].length {
+			result += j * blocks[i].id
+			blocks[i].used += 1
+			j++
+		}
+
+		for blocks[i].freeUsed != blocks[i].free {
+			for m := len(blocks) - 1; m >= 0; m-- {
+				if blocks[m].used != blocks[m].length {
+					result += j * blocks[m].id
+					blocks[m].used += 1
+					break
+				}
+			}
+
+			blocks[i].freeUsed += 1
+			j++
+		}
+	}
+
+	return result
+}
+
+func findBlockWithLE(blocks []Block, size int, self int) int {
+	for i := len(blocks) - 1; i >= 0; i-- {
+		if blocks[i].id != self && blocks[i].length <= size {
+			return i
+		}
+	}
+
+	return -1
+}
+
+func getIndex(blocks []Block, id int) int {
+	for i, block := range blocks {
+		if block.id == id {
+			return i
+		}
+	}
+
+	return -1
+}
+
+func printBlocks(blocks []Block) {
+	for i := 0; i < len(blocks); i++ {
+		for j := 0; j < blocks[i].length; j++ {
+			fmt.Print("|", blocks[i].id)
+		}
+		for j := 0; j < blocks[i].free; j++ {
+			fmt.Print("|", ".")
+		}
+	}
+	fmt.Println()
+}
+
+func Part2(input structuredInput) int {
+	var result = 0
+
+	var blocks = Part1CreateBlocks(input)
+
+	var index int
+	var freeHost int
+	var freeUser int
+	var j int
+
+	for i := len(blocks) - 1; i >= 0; i-- {
+		index = getIndex(blocks, i)
+		for j := 0; j < index; j++ {
+			if blocks[j].free >= blocks[index].length {
+				freeHost = blocks[j].free
+				freeUser = blocks[index].free
+				blocks[j].free = 0
+				blocks[index].free = freeHost - blocks[index].length
+				blocks = slices.Insert(blocks, j+1, blocks[index])
+				blocks[index+1].id = -1
+				blocks[index+1].free = freeUser + blocks[index+1].length
+				blocks[index+1].length = 0
+				break
+			}
+		}
+	}
+
+	j = 0
+	for i := 0; i < len(blocks); i++ {
+		for m := 0; m < blocks[i].length; m++ {
+			result += j * blocks[i].id
+			j++
+		}
+		j += blocks[i].free
+	}
+
+	return result
+}
+
+func main() {
+	var start time.Time
+	var elapsed time.Duration = 0
+	input, err := LoadInput(FILE_PATH)
+	if err != nil {
+		fmt.Println("Error loading input:", err)
+		return
+	}
+
+	structuredInput := TransformInput(input)
+	fmt.Println("Structured Input:", structuredInput)
+
+	start = time.Now()
+	fmt.Println("Solution Part 1: ", Part1(structuredInput))
+	elapsed = time.Since(start)
+	fmt.Printf("Part 1 took %s\n", elapsed)
+
+	start = time.Now()
+	fmt.Println("Solution Part 2: ", Part2(structuredInput))
+	elapsed = time.Since(start)
+	fmt.Printf("Part 2 took %s\n", elapsed)
+}

09/sample.txt

@@ -0,0 +1 @@
+354631466260