2023/03

2023/03/go.mod

@@ -0,0 +1,11 @@
+module zv0n/advent_of_code/2023/03
+
+go 1.21.4
+
+require (
+	github.com/fatih/color v1.16.0 // indirect
+	github.com/mattn/go-colorable v0.1.13 // indirect
+	github.com/mattn/go-isatty v0.0.20 // indirect
+	github.com/thoas/go-funk v0.9.3 // indirect
+	golang.org/x/sys v0.14.0 // indirect
+)

2023/03/go.sum

@@ -0,0 +1,19 @@
+github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/fatih/color v1.16.0 h1:zmkK9Ngbjj+K0yRhTVONQh1p/HknKYSlNT+vZCzyokM=
+github.com/fatih/color v1.16.0/go.mod h1:fL2Sau1YI5c0pdGEVCbKQbLXB6edEj1ZgiY4NijnWvE=
+github.com/mattn/go-colorable v0.1.13 h1:fFA4WZxdEF4tXPZVKMLwD8oUnCTTo08duU7wxecdEvA=
+github.com/mattn/go-colorable v0.1.13/go.mod h1:7S9/ev0klgBDR4GtXTXX8a3vIGJpMovkB8vQcUbaXHg=
+github.com/mattn/go-isatty v0.0.16/go.mod h1:kYGgaQfpe5nmfYZH+SKPsOc2e4SrIfOl2e/yFXSvRLM=
+github.com/mattn/go-isatty v0.0.20 h1:xfD0iDuEKnDkl03q4limB+vH+GxLEtL/jb4xVJSWWEY=
+github.com/mattn/go-isatty v0.0.20/go.mod h1:W+V8PltTTMOvKvAeJH7IuucS94S2C6jfK/D7dTCTo3Y=
+github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
+github.com/stretchr/testify v1.4.0/go.mod h1:j7eGeouHqKxXV5pUuKE4zz7dFj8WfuZ+81PSLYec5m4=
+github.com/thoas/go-funk v0.9.3 h1:7+nAEx3kn5ZJcnDm2Bh23N2yOtweO14bi//dvRtgLpw=
+github.com/thoas/go-funk v0.9.3/go.mod h1:+IWnUfUmFO1+WVYQWQtIJHeRRdaIyyYglZN7xzUPe4Q=
+golang.org/x/sys v0.0.0-20220811171246-fbc7d0a398ab/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.6.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.14.0 h1:Vz7Qs629MkJkGyHxUlRHizWJRG2j8fbQKjELVSNhy7Q=
+golang.org/x/sys v0.14.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/yaml.v2 v2.2.2/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=

2023/03/main.go

@@ -0,0 +1,159 @@
+package main
+
+import (
+	"bufio"
+	"fmt"
+	"os"
+	"unicode"
+
+	"github.com/fatih/color"
+	"github.com/thoas/go-funk"
+)
+
+type EnginePart struct {
+	number     uint64
+	line       uint64
+	startIndex uint64
+	endIndex   uint64
+}
+
+func readFileLines(filename string) ([]string, error) {
+	var lines []string
+
+	file, err := os.Open(filename)
+	if err != nil {
+		return lines, err
+	}
+	fileScanner := bufio.NewScanner(file)
+	fileScanner.Split(bufio.ScanLines)
+
+	for fileScanner.Scan() {
+		lines = append(lines, fileScanner.Text())
+	}
+
+	return lines, nil
+}
+
+func getEngineParts(lines *[]string) []EnginePart {
+	var result []EnginePart
+	var tmpPart EnginePart
+	for lineIdx := 0; lineIdx < len(*lines); lineIdx++ {
+		line := &(*lines)[lineIdx]
+		tmpPart.number = 0
+		tmpPart.line = uint64(lineIdx)
+		numStarted := false
+		for charIdx, char := range *line {
+			if unicode.IsDigit(char) {
+				if !numStarted {
+					tmpPart.startIndex = uint64(charIdx)
+					numStarted = true
+				}
+				tmpPart.number *= 10
+				tmpPart.number += uint64(char) - uint64('0')
+			} else if numStarted {
+				numStarted = false
+				tmpPart.endIndex = uint64(charIdx) - 1
+				result = append(result, tmpPart)
+				tmpPart.number = 0
+			}
+		}
+		if numStarted {
+			tmpPart.endIndex = uint64(len(*line)) - 1
+			result = append(result, tmpPart)
+			tmpPart.number = 0
+		}
+	}
+	return result
+}
+
+func hasSymbol(line *string, startIndex uint64, endIndex uint64) bool {
+	for i := startIndex; i <= endIndex; i++ {
+		if (*line)[i] != '.' && !unicode.IsDigit(rune((*line)[i])) {
+			return true
+		}
+	}
+	return false
+}
+
+func getValidEngineParts(parts *[]EnginePart, lines *[]string) []uint64 {
+	var validParts []uint64
+	for i := 0; i < len(*parts); i++ {
+		part := &(*parts)[i]
+		startIndex := part.startIndex
+		endIndex := part.endIndex
+		if startIndex > 0 {
+			startIndex--
+		}
+		if endIndex < uint64(len((*lines)[0]))-1 {
+			endIndex++
+		}
+		for i := part.line - 1; i != part.line+2; i++ {
+			if i >= uint64(len(*lines)) {
+				continue
+			}
+			if hasSymbol(&(*lines)[i], startIndex, endIndex) {
+				validParts = append(validParts, part.number)
+				break
+			}
+		}
+	}
+	return validParts
+}
+
+func hasTwoAdjecent(parts *[]EnginePart, lineIdx uint64, charIdx uint64) (bool, []EnginePart) {
+	var result []EnginePart
+	for i := 0; i < len(*parts); i++ {
+		part := &(*parts)[i]
+		if part.line >= lineIdx-1 && part.line <= lineIdx+1 {
+			if part.startIndex <= charIdx+1 && part.endIndex >= charIdx-1 {
+				result = append(result, *part)
+			}
+		}
+	}
+	return len(result) == 2, result
+}
+
+func getGears(parts *[]EnginePart, lines *[]string) []uint64 {
+	var result []uint64
+	for lineIdx := 0; lineIdx < len(*lines); lineIdx++ {
+		line := &((*lines)[lineIdx])
+		for charIdx, char := range *line {
+			if char == '*' {
+				valid, engineParts := hasTwoAdjecent(parts, uint64(lineIdx), uint64(charIdx))
+				if valid {
+					result = append(result, engineParts[0].number*engineParts[1].number)
+				}
+			}
+		}
+	}
+	return result
+}
+
+func main() {
+	redPrint := color.New(color.FgRed)
+	yellowPrint := color.New(color.FgYellow)
+	if len(os.Args) < 2 {
+		redPrint.Fprintln(os.Stderr, "You must provide the input file")
+		os.Exit(1)
+	}
+	lines, err := readFileLines(os.Args[1])
+	if err != nil {
+		redPrint.Fprintln(os.Stderr, "Could not read input file")
+		os.Exit(1)
+	}
+	engineParts := getEngineParts(&lines)
+
+	validParts := getValidEngineParts(&engineParts, &lines)
+	validPartSum := funk.Reduce(validParts, func(acc, elem uint64) uint64 { return acc + elem }, uint64(0))
+
+	fmt.Print("Part 1: ")
+	yellowPrint.Print(validPartSum)
+	fmt.Println()
+
+	gearRatios := getGears(&engineParts, &lines)
+	gearRatiosSum := funk.Reduce(gearRatios, func(acc, elem uint64) uint64 { return acc + elem }, uint64(0))
+
+	fmt.Print("Part 2: ")
+	yellowPrint.Print(gearRatiosSum)
+	fmt.Println()
+}