Solve 2025 day 1 part 1

.github/workflows/2024.yml

@@ -1,43 +0,0 @@
-on:
-  - push
-
-name: Advent of Code 2024
-
-jobs:
-  ci:
-    strategy:
-      matrix:
-        python-version:
-          - "3.12"
-          - "3.13"
-
-    name: Continuous Integration
-    runs-on: ubuntu-latest
-
-    steps:
-      - uses: actions/checkout@v4
-
-      - uses: actions/setup-python@v5
-        with:
-          python-version: ${{ matrix.python-version }}
-
-      - name: Install uv
-        uses: astral-sh/setup-uv@v3
-        with:
-          enable-cache: true
-          cache-dependency-glob: "2024/uv.lock"
-
-      - name: Check formatting
-        working-directory: "2024"
-        run: >
-          uv run ruff format --check
-
-      - name: Run lints
-        working-directory: "2024"
-        run: >
-          uv run ruff check
-
-      - name: Run tests
-        working-directory: "2024"
-        run: >
-          uv run pytest tests

2025/README.md

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+# Advent of Code 2025
+
+New year, new challenge. With the shorter year, I'm going to try to use a different language every
+day, restricting myself to programming languages my employer uses in production. Let's call it the
+**Full Stack Challenge**.

2025/day01/sample.txt

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+L68
+L30
+R48
+L5
+R60
+L55
+L1
+L99
+R14
+L82

2025/day01/solve.nix

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+{
+    solve = input_file:
+        let
+            data = builtins.readFile input_file;
+            lines = builtins.filter (s: s != "" && builtins.isString s) (builtins.split "\n" data);
+
+            mod = a: b: a - (a / b) * b;
+
+            recurse = list: position:
+                let
+                    first = builtins.head list;
+                    # This is not guaranteed to work but it does
+                    num_part = builtins.substring 1 999 first;
+                    num = builtins.fromJSON num_part;
+                    next = if (builtins.substring 0 1 first) == "R"
+                        then
+                            position + num
+                        else
+                            position - num;
+
+                    new_position = mod ((mod next 100) + 100) 100; 
+                    
+                    score = if new_position == 0 then 1 else 0;
+                in
+                    if list == [] then
+                        0
+                    else
+                        score + (recurse (builtins.tail list) new_position);
+        in
+            recurse lines 50;
+}