feat: solve part one

internal/2017/DayTwo/code.go

@@ -0,0 +1,51 @@
+package daytwo
+
+import (
+	"advent-of-code/internal/registry"
+	"os"
+	"strconv"
+	"strings"
+)
+
+func init() {
+	registry.Register("2017D2", ParseInput, PartOne, PartTwo)
+}
+
+func ParseInput(filepath string) [][]int {
+	content, _ := os.ReadFile(filepath)
+	lines := strings.Split(string(content), "\n")
+	result := make([][]int, 0, len(lines))
+
+	for _, line := range lines {
+		fields := strings.Fields(line)
+		row := make([]int, 0, len(fields))
+		for _, field := range fields {
+			num, _ := strconv.Atoi(field)
+			row = append(row, num)
+		}
+		result = append(result, row)
+	}
+
+	return result
+}
+
+func PartOne(data [][]int) int {
+	sum := 0
+	for _, row := range data {
+		min, max := row[0], row[0]
+		for _, value := range row[1:] {
+			if value < min {
+				min = value
+			}
+			if value > max {
+				max = value
+			}
+		}
+		sum += max - min
+	}
+	return sum
+}
+
+func PartTwo(data [][]int) int {
+	return 0
+}

internal/2017/DayTwo/code_test.go

@@ -0,0 +1,17 @@
+package daytwo
+
+import "testing"
+
+var testInput = [][]int{
+	{5, 1, 9, 5},
+	{7, 5, 3},
+	{2, 4, 6, 8},
+}
+
+func TestPartOne(t *testing.T) {
+	got := PartOne(testInput)
+	expected := 18
+	if got != expected {
+		t.Errorf("PartOne() = %d, want %d", got, expected)
+	}
+}