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())
+}

2025/Day-02/day02.go

@@ -0,0 +1,97 @@
+package main
+
+import (
+	"fmt"
+	"os"
+	"strconv"
+	"strings"
+)
+
+func partOne() int {
+	file, err := os.ReadFile("input.txt")
+	if err != nil {
+		os.Exit(1)
+	}
+	tot := 0
+	for _, ids := range strings.Split(string(file), ",") {
+		r := strings.Split(ids, "-")
+		s, _ := strconv.Atoi(r[0])
+		e, _ := strconv.Atoi(r[1])
+
+		for i := s; i <= e; i++ {
+			curId := strconv.Itoa(i)
+			if len(curId)%2 != 0 {
+				continue
+			}
+			half := (len(curId) / 2)
+			a := ""
+			b := ""
+			if len(curId) == 2 {
+				a = string(curId[0])
+				b = string(curId[1])
+			} else {
+				a = string(curId[:half])
+				b = string(curId[half:])
+			}
+			if a == b {
+				tot += i
+			}
+		}
+	}
+	return tot
+}
+
+func toChunks(in string, l int) []string {
+	nChunks := len(in) / l
+	ret := make([]string, nChunks)
+	for i := 0; i < nChunks; i++ {
+		ret[i] = in[(l * i):(l*i + l)]
+	}
+	return ret
+}
+
+func allEqual(a []string) bool {
+	for i := 1; i < len(a); i++ {
+		if a[i] != a[0] {
+			return false
+		}
+	}
+	return true
+}
+
+func partTwo() int {
+	file, err := os.ReadFile("input.txt")
+	if err != nil {
+		os.Exit(1)
+	}
+	tot := 0
+	for _, ids := range strings.Split(string(file), ",") {
+		r := strings.Split(ids, "-")
+		s, _ := strconv.Atoi(r[0])
+		e, _ := strconv.Atoi(r[1])
+
+		for i := s; i <= e; i++ {
+			curId := strconv.Itoa(i)
+			valid := 0
+			for c := 1; c <= len(curId)/2; c++ {
+				if len(curId)%c != 0{
+					continue
+				}
+				chunks := toChunks(curId, c)
+				if allEqual(chunks) {
+					valid += 1
+					break
+				}
+			}
+			if valid != 0 {
+				tot += i
+			}
+		}
+	}
+	return tot
+}
+
+func main() {
+	fmt.Println(partOne())
+	fmt.Println(partTwo())
+}