2025 day 1 and 2

2025/Day-01/day01.go

@@ -0,0 +1,94 @@
+package main
+
+import (
+	"bufio"
+	"fmt"
+	"log"
+	"os"
+	"strconv"
+)
+
+func partOne() int {
+	file, err := os.Open("input.txt")
+	if err != nil {
+		log.Fatalf("failed to open file: %s", err)
+	}
+	defer file.Close()
+	scanner := bufio.NewScanner(file)
+	var startPos int = 50
+	code := 0
+	for scanner.Scan() {
+		line := scanner.Text()
+		dir := string(line[0])
+		num, _ := strconv.Atoi(string(line[1:]))
+		for num > 99 {
+			num -= 100
+		}
+		switch dir {
+		case "L":
+			if (startPos - num) < 0 {
+				startPos = 99 - (num - startPos - 1)
+			} else {
+				startPos -= num
+			}
+		case "R":
+			if (startPos + num) > 99 {
+				startPos = 0 + (num - (100 - startPos))
+			} else {
+				startPos += num
+			}
+		}
+		if startPos == 0 {
+			code++
+		}
+	}
+	return code
+}
+
+func partTwo() int {
+	file, err := os.Open("input.txt")
+	if err != nil {
+		log.Fatalf("failed to open file: %s", err)
+	}
+	defer file.Close()
+	scanner := bufio.NewScanner(file)
+	var startPos int = 50
+	code := 0
+	for scanner.Scan() {
+		line := scanner.Text()
+		dir := string(line[0])
+		num, _ := strconv.Atoi(string(line[1:]))
+		for num > 99 {
+			num -= 100
+			code += 1
+		}
+		switch dir {
+		case "L":
+			for i := 0; i<num; i++ {
+				startPos--
+				if startPos < 0 {
+					startPos = 99
+				}
+				if startPos == 0 {
+					code++
+				}
+			}
+		case "R":
+			for i := 0; i<num; i++ {
+				startPos++
+				if startPos > 99 {
+					startPos = 0
+				}
+				if startPos == 0 {
+					code++
+				}
+			}
+		}
+	}
+	return code
+}
+
+func main() {
+	fmt.Println(partOne())
+	fmt.Println(partTwo())
+}