feat: solve part one

internal/2018/DayFive/code.go

@@ -0,0 +1,41 @@
+package dayfive
+
+import (
+	"advent-of-code/internal/registry"
+	"os"
+	"unicode"
+)
+
+func init() {
+	registry.Register("2018D5", ParseInput, PartOne, PartTwo)
+}
+
+func ParseInput(filepath string) string {
+	content, _ := os.ReadFile(filepath)
+	return string(content)
+}
+
+func PartOne(data string) int {
+	stack := []rune{}
+
+	for _, char := range data {
+		if len(stack) == 0 {
+			stack = append(stack, char)
+			continue
+		}
+
+		top := stack[len(stack)-1]
+
+		if unicode.ToLower(top) == unicode.ToLower(char) && top != char {
+			stack = stack[:len(stack)-1]
+		} else {
+			stack = append(stack, char)
+		}
+	}
+
+	return len(stack)
+}
+
+func PartTwo(data string) int {
+	return 0
+}