From 2910d6313ccae8f01ff8d1a8799230926593e0eb Mon Sep 17 00:00:00 2001
From: Nico <nico@astolfo.org>
Date: Tue, 2 Dec 2025 00:17:21 +1100
Subject: [PATCH] add aoc 2025 day 1 solution

---
 2025/1/README.md |  8 ++++++
 2025/1/input.txt | 10 +++++++
 2025/1/main.go   | 71 ++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 89 insertions(+)
 create mode 100644 2025/1/README.md
 create mode 100644 2025/1/input.txt
 create mode 100644 2025/1/main.go

diff --git a/2025/1/README.md b/2025/1/README.md
new file mode 100644
index 0000000..42e6015
--- /dev/null
+++ b/2025/1/README.md
@@ -0,0 +1,8 @@
+# aoc 2025 day 1
+
+run with:
+```sh
+go run main.go
+```
+
+you will need to put your input into input.txt first though. example is put in input.txt currently
diff --git a/2025/1/input.txt b/2025/1/input.txt
new file mode 100644
index 0000000..53287c7
--- /dev/null
+++ b/2025/1/input.txt
@@ -0,0 +1,10 @@
+L68
+L30
+R48
+L5
+R60
+L55
+L1
+L99
+R14
+L82
diff --git a/2025/1/main.go b/2025/1/main.go
new file mode 100644
index 0000000..bbb6ee6
--- /dev/null
+++ b/2025/1/main.go
@@ -0,0 +1,71 @@
+package main
+
+import (
+	"bufio"
+	"fmt"
+	"os"
+	"strconv"
+	"strings"
+)
+
+func main() {
+	rotations := Decode("input.txt")
+
+	rotation := 50
+	zeroamount := 0
+
+	for _, i := range rotations {
+		b := i % 100 // for large number rotations eg. L392 -> L92
+
+		r := rotation + b
+		if r > 99 {
+			r = r - 100
+		} else if r < 0 {
+			r = r + 100
+		}
+
+		if r == 0 {
+			zeroamount = zeroamount + 1
+		}
+
+		fmt.Printf("rotation is now at: %d+%d=%d, rotation %d\n", rotation, b, r, i)
+		rotation = r
+	}
+
+	fmt.Println("zero amount is:", zeroamount)
+
+}
+
+func Decode(filename string) []int {
+	f, err := os.Open(filename)
+
+	if err != nil {
+		panic(err)
+	}
+
+	defer f.Close()
+
+	scanner := bufio.NewScanner(f)
+
+	var rotations []int
+
+	for scanner.Scan() {
+		if strings.Contains(scanner.Text(), "L") {
+			a := strings.Replace(scanner.Text(), "L", "", 1)
+
+			b, _ := strconv.Atoi(a)
+			c := b-b*2 // makes negative, this is so janky
+			rotations = append(rotations, c)
+			fmt.Printf("converted %s to int %d\n", scanner.Text(), c)
+
+		} else if strings.Contains(scanner.Text(), "R") {
+			a := strings.Replace(scanner.Text(), "R", "", 1)
+
+			b, _ := strconv.Atoi(a)
+			rotations = append(rotations, b)
+			fmt.Printf("converted %s to int %d\n", scanner.Text(), b)
+		}
+	}
+
+	return rotations
+}