2nd: remove redundancy

cmd/main.go

@@ -1,7 +1,14 @@
 package main
 
-import "adventofcode/pkg/one"
+import (
+	"adventofcode/pkg/one"
+	"adventofcode/pkg/two"
+	"fmt"
+)
 
 func main() {
+	fmt.Println("Day 1")
 	one.Run()
+	fmt.Println("Day 2")
+	two.Run()
 }

pkg/one/one.go

@@ -58,9 +58,6 @@ func secondSolution() {
 	b := make([]int, 3)
 	numbers := getNumbers()
 
-	a = numbers[0:3]
-	b = numbers[1:4]
-
 	for i := 0; i < len(numbers); i++ {
 		if i+4 <= len(numbers) {
 			a = numbers[i : i+3]

pkg/two/two.go

@@ -0,0 +1,82 @@
+package two
+
+import (
+	"bufio"
+	"fmt"
+	"log"
+	"os"
+	"strconv"
+	"strings"
+)
+
+var depth int
+var horizontalPosition int
+var aim int
+
+func Run() {
+	commands := readInput()
+	fmt.Printf("1st final position: %d\n", solve(commands, false))
+	fmt.Printf("2nd final position: %d\n", solve(commands, true))
+}
+
+func solve(commands []string, alt bool) int {
+	depth = 0
+	horizontalPosition = 0
+	aim = 0
+
+	for _, v := range commands {
+		command := strings.Split(v, " ")
+		switch command[0] {
+		case "forward":
+			i, _ := strconv.Atoi(command[1])
+			forward(i, alt)
+		case "up":
+			i, _ := strconv.Atoi(command[1])
+			up(i, alt)
+		case "down":
+			i, _ := strconv.Atoi(command[1])
+			down(i, alt)
+		}
+	}
+	return horizontalPosition * depth
+}
+
+func up(d int, alt bool) {
+	if !alt {
+		depth -= d
+	} else {
+		aim -= d
+	}
+}
+
+func down(d int, alt bool) {
+	if !alt {
+		depth += d
+	} else {
+		aim += d
+	}
+}
+
+func forward(d int, alt bool) {
+	horizontalPosition += d
+	if alt {
+		depth += aim * d
+	}
+}
+
+func readInput() []string {
+	file, err := os.Open("./pkg/two/input.txt")
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer file.Close()
+	commands := make([]string, 0)
+	scanner := bufio.NewScanner(file)
+	for scanner.Scan() {
+		commands = append(commands, scanner.Text())
+	}
+	if err := scanner.Err(); err != nil {
+		log.Fatal(err)
+	}
+	return commands
+}