[ADD] main: Added day 13 solution

13/main.go

@@ -0,0 +1,154 @@
+package main
+
+import (
+	"bufio"
+	"fmt"
+	"os"
+	"strconv"
+	"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 Vector2 struct {
+	x int
+	y int
+}
+
+type Puzzle struct {
+	buttonA Vector2
+	buttonB Vector2
+	price   Vector2
+}
+
+type structuredInput = []Puzzle
+
+func TransformInput(lines []string) structuredInput {
+	var result = make([]Puzzle, 0)
+	var numb int
+	var buttonA Vector2
+	var buttonB Vector2
+	var prize Vector2
+	var j int
+	for i := 0; i < len(lines); i += 4 {
+		buttonA = Vector2{}
+		numb, _ = strconv.Atoi(lines[i][len("Button A: X+") : len("Button A: X+")+2])
+		buttonA.x = numb
+		numb, _ = strconv.Atoi(lines[i][len("Button A: X+")+5 : len("Button A: X+")+8])
+		buttonA.y = numb
+
+		buttonB = Vector2{}
+		numb, _ = strconv.Atoi(lines[i+1][len("Button A: X+") : len("Button A: X+")+2])
+		buttonB.x = numb
+		numb, _ = strconv.Atoi(lines[i+1][len("Button A: X+")+5 : len("Button A: X+")+8])
+		buttonB.y = numb
+
+		prize = Vector2{}
+		j = 0
+		for ; j < len(lines[i+2]); j++ {
+			if lines[i+2][j] == ',' {
+				break
+			}
+		}
+		numb, _ = strconv.Atoi(lines[i+2][len("Prize: X="):j])
+		prize.x = numb
+		numb, _ = strconv.Atoi(lines[i+2][j+4:])
+		prize.y = numb
+
+		result = append(result, Puzzle{buttonA, buttonB, prize})
+	}
+
+	return result
+}
+
+func calculatePuzzleSolution(puzzle Puzzle) int {
+	var mf float64 = 0
+	var m int
+	var n int
+
+	// This case would be possible if a and b are multiple of each other so either b or a must be 0 this is never the case
+	if puzzle.buttonB.x*puzzle.buttonA.y == puzzle.buttonA.x*puzzle.buttonB.y || puzzle.buttonB.x*puzzle.buttonB.y == 0 {
+		return 0
+	}
+
+	mf = float64(puzzle.buttonB.x*puzzle.price.y-puzzle.price.x*puzzle.buttonB.y) / float64(puzzle.buttonB.x*puzzle.buttonA.y-puzzle.buttonA.x*puzzle.buttonB.y)
+	m = int(mf)
+
+	if float64(m) != mf {
+		return 0
+	}
+
+	n = (puzzle.price.x - puzzle.buttonA.x*m) / puzzle.buttonB.x
+
+	return m*3 + n
+}
+
+func Part1(input structuredInput) int {
+	var result = 0
+
+	for _, puzzle := range input {
+		result += calculatePuzzleSolution(puzzle)
+	}
+
+	return result
+}
+
+func Part2(input structuredInput) int {
+	var result = 0
+
+	for i := 0; i < len(input); i++ {
+		input[i].price.x += 10000000000000
+		input[i].price.y += 10000000000000
+	}
+
+	for _, puzzle := range input {
+		result += calculatePuzzleSolution(puzzle)
+	}
+
+	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)
+}

13/sample.txt

@@ -0,0 +1,15 @@
+Button A: X+94, Y+34
+Button B: X+22, Y+67
+Prize: X=8400, Y=5400
+
+Button A: X+26, Y+66
+Button B: X+67, Y+21
+Prize: X=12748, Y=12176
+
+Button A: X+17, Y+86
+Button B: X+84, Y+37
+Prize: X=7870, Y=6450
+
+Button A: X+69, Y+23
+Button B: X+27, Y+71
+Prize: X=18641, Y=10279