Optimise the snot out of 2024.06

challenges/2024/06-guardGallivant/README.md

@@ -3,3 +3,28 @@
 Part 2 is:
 * higher than 456
 * less than 1689
+
+The first implementation of part 2 took 15 minutes to run.
+
+* Turning `visited_sequence` in `trace` into a set instead of a list cut this to 60 seconds
+* Starting immediately in front of the new obstacle when testing positions to put said new obstacle in cut this to 20 seconds
+* Removing a load of maps and type wranging to turn the fully generic `gridutil.add` (and counterparts) into a more limited but much faster function took this to ~16 seconds
+
+Before:
+
+```py
+def _coordmap(a: AnyCoordinate, b: AnyCoordinate, fn: Callable) -> AnyCoordinate:
+    at = type(a)
+    return at(*map(fn, zip(a, b)))
+
+def add(a: AnyCoordinate, b: AnyCoordinate) -> AnyCoordinate:
+    return _coordmap(a, b, lambda x: x[0] + x[1])
+```
+
+After:
+
+
+```py
+def add(a: Coordinate, b: Coordinate) -> Coordinate:
+    return Coordinate(a.x + b.x, a.y + b.y)
+```

challenges/2024/06-guardGallivant/main.py

@@ -63,11 +63,11 @@ def two(instr: str) -> int:
     seq = trace(g, start_pos, 0)
     known_blocks = set()
 
-    for (pos, _) in tqdm(seq, file=sys.stderr):
+    for (pos, dir) in tqdm(seq, file=sys.stderr):
         assert pos in g, "pos off the rails"
         g[pos] = "#"
         try:
-            trace(g, start_pos, 0)
+            trace(g, coord.add(pos, coord.mult(dirs[dir].delta(), -1)), dir)
         except LoopEncounteredException:
             known_blocks.add(pos)
         g[pos] = "."

challenges/2024/benchmarks.jsonl

@@ -8,5 +8,5 @@
 {"day": 4, "part": 2, "runner": "py", "min": 0.05280470848083496, "max": 0.06299543380737305, "avg": 0.05627016305923462, "n": 100}
 {"day": 5, "part": 1, "runner": "py", "min": 0.02001357078552246, "max": 0.030559301376342773, "avg": 0.02152919292449951, "n": 100}
 {"day": 5, "part": 2, "runner": "py", "min": 0.02507805824279785, "max": 0.03197765350341797, "avg": 0.027084295749664308, "n": 100}
-{"day": 6, "part": 1, "runner": "py", "min": 0.0671079158782959, "max": 0.0671079158782959, "avg": 0.0671079158782959, "n": 1}
-{"day": 6, "part": 2, "runner": "py", "min": 61.63975167274475, "max": 61.63975167274475, "avg": 61.63975167274475, "n": 1}
+{"day": 6, "part": 1, "runner": "py", "min": 0.05790352821350098, "max": 0.06762170791625977, "avg": 0.061776439348856606, "n": 6}
+{"day": 6, "part": 2, "runner": "py", "min": 15.881408452987671, "max": 17.086341857910156, "avg": 16.64130985736847, "n": 6}

gridutil/coord.py

@@ -9,22 +9,16 @@ Coordinate3 = namedtuple("Coordinate3", ["x", "y", "z"])
 AnyCoordinate = Coordinate | Coordinate3
 
 
-def _coordmap(a: AnyCoordinate, b: AnyCoordinate, fn: Callable) -> AnyCoordinate:
-    at = type(a)
-    return at(*map(fn, zip(a, b)))
+def add(a: Coordinate, b: Coordinate) -> Coordinate:
+    return Coordinate(a.x + b.x, a.y + b.y)
 
 
-def add(a: AnyCoordinate, b: AnyCoordinate) -> AnyCoordinate:
-    return _coordmap(a, b, lambda x: x[0] + x[1])
+def sub(a: Coordinate, b: Coordinate) -> Coordinate:
+    return Coordinate(a.x - b.x, a.y - b.y)
 
 
-def sub(a: AnyCoordinate, b: AnyCoordinate) -> AnyCoordinate:
-    return _coordmap(a, b, lambda x: x[0] - x[1])
-
-
-def mult(a: AnyCoordinate, b: Number) -> AnyCoordinate:
-    at = type(a)
-    return at(*map(lambda x: x * b, a))
+def mult(a: Coordinate, b: Number) -> Coordinate:
+    return Coordinate(a.x * b, a.y * b)
 
 
 def manhattan_dist(a: AnyCoordinate, b: AnyCoordinate) -> Number: