Implement 2024 day 17 part 1

2024/src/aoc/days/day16.py

@@ -32,7 +32,7 @@ class DayRunner(CombinedRunner):
                 heapq.heappush(todo, (dist, x, y, dx, dy))
             elif best[x, y, dx, dy][0] == dist:
                 best[x, y, dx, dy][1].append((cx, cy, cdx, cdy))
-            
+
         shortest_dist = None
         finishes = set()
 

2024/src/aoc/days/day17.py

@@ -0,0 +1,60 @@
+import re
+
+from . import SeparateRunner
+
+
+class DayRunner(SeparateRunner):
+    @classmethod
+    def part1(cls, input: str) -> str:
+        numbers = re.findall(r"\d+", input)
+
+        register_a, register_b, register_c = map(int, numbers[:3])
+        program = list(map(int, numbers[3:]))
+
+        ip = 0
+        out = []
+
+        def combo(index: int) -> int:
+            match program[index]:
+                case 0:
+                    return 0
+                case 1:
+                    return 1
+                case 2:
+                    return 2
+                case 3:
+                    return 3
+                case 4:
+                    return register_a
+                case 5:
+                    return register_b
+                case 6:
+                    return register_c
+
+        while ip < len(program):
+            match program[ip]:
+                case 0:  # adv
+                    register_a = register_a // 2 ** combo(ip + 1)
+                case 1:  # bxl
+                    register_b ^= program[ip + 1]
+                case 2:  # bst
+                    register_b = combo(ip + 1) & 0x7
+                case 3:  # jnz
+                    if register_a != 0:
+                        ip = program[ip + 1]
+                        continue
+                case 4:  # bxc
+                    register_b ^= register_c
+                case 5:  # out
+                    out.append(combo(ip + 1) & 7)
+                case 6:  # bdv
+                    register_b = register_a // 2 ** combo(ip + 1)
+                case 7:  # cdv
+                    register_c = register_a // 2 ** combo(ip + 1)
+            ip += 2
+
+        return ",".join(map(str, out))
+
+    @classmethod
+    def part2(cls, input: str) -> str:
+        pass

2024/tests/samples/17.txt

@@ -0,0 +1,5 @@
+Register A: 729
+Register B: 0
+Register C: 0
+
+Program: 0,1,5,4,3,0

2024/tests/test_day16.py

@@ -14,3 +14,14 @@ from . import get_data
 )
 def test_sample_part1(data: str, result: int) -> None:
     assert DayRunner.part1(data) == result
+
+
+@pytest.mark.parametrize(
+    "data,result",
+    [
+        (get_data(16, 1), 45),
+        (get_data(16, 2), 64),
+    ],
+)
+def test_sample_part2(data: str, result: int) -> None:
+    assert DayRunner.part2(data) == result

2024/tests/test_day17.py

@@ -0,0 +1,7 @@
+from aoc.days.day17 import DayRunner
+
+from . import get_data
+
+
+def test_sample_part1() -> None:
+    assert DayRunner.part1(get_data(17)) == "4,6,3,5,6,3,5,2,1,0"