Implement 2024 day 21 part 1

2024/tests/samples/21.txt

@@ -0,0 +1,5 @@
+029A
+980A
+179A
+456A
+379A

2024/tests/test_day21.py

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+import pytest
+
+from aoc.days.day21 import (
+    DayRunner,
+    encode_shortest_dirpad,
+    encode_shortest_numpad,
+)
+
+from . import get_data
+
+
+def test_encode_shortest_numpad() -> None:
+    assert encode_shortest_numpad("029A") in (
+        "<A^A>^^AvvvA",
+        "<A^A^>^AvvvA",
+        "<A^A^^>AvvvA",
+    )
+
+
+def test_encode_shortest_dirpad() -> None:
+    numpad_encoded = encode_shortest_numpad("029A")
+    assert len(encode_shortest_dirpad(numpad_encoded)) == len(
+        "v<<A>>^A<A>AvA<^AA>A<vAAA>^A"
+    )
+
+
+@pytest.mark.parametrize(
+    "code,answer",
+    [
+        (
+            "029A",
+            "<vA<AA>>^AvAA<^A>A<v<A>>^AvA^A<vA>^A<v<A>^A>AAvA^A<v<A>A>^AAAvA<^A>A",
+        ),
+        ("980A", "<v<A>>^AAAvA^A<vA<AA>>^AvAA<^A>A<v<A>A>^AAAvA<^A>A<vA>^A<A>A"),
+        (
+            "179A",
+            "<v<A>>^A<vA<A>>^AAvAA<^A>A<v<A>>^AAvA^A<vA>^AA<A>A<v<A>A>^AAAvA<^A>A",
+        ),
+        ("456A", "<v<A>>^AA<vA<A>>^AAvAA<^A>A<vA>^A<A>A<vA>^A<A>A<v<A>A>^AAvA<^A>A"),
+        ("379A", "<v<A>>^AvA^A<vA<AA>>^AAvA<^A>AAvA^A<vA>^AA<A>A<v<A>A>^AAAvA<^A>A"),
+    ],
+)
+def test_encode_shortest_dirpad_twice(code: str, answer: str) -> None:
+    numpad_encoded = encode_shortest_numpad(code)
+    robot1 = encode_shortest_dirpad(numpad_encoded)
+    robot2 = encode_shortest_dirpad(robot1)
+    assert len(robot2) == len(answer)
+
+
+def test_sample_part1() -> None:
+    assert DayRunner.part1(get_data(21)) == 126384