Clean 2023.

2023/day2.py

@@ -1,6 +1,5 @@
-import operator
+import math
 import sys
-from functools import reduce
 from typing import Literal, TypeAlias, cast
 
 CubeType: TypeAlias = Literal["red", "blue", "green"]
@@ -36,9 +35,8 @@ print(f"answer 1 is {answer_1}")
 
 # part 2
 answer_2 = sum(
-    reduce(
+    math.prod(
-        operator.mul,
+        max(cube_set.get(cube, 0) for cube_set in set_of_cubes) for cube in MAX_CUBES
-        (max(cube_set.get(cube, 0) for cube_set in set_of_cubes) for cube in MAX_CUBES),
     )
     for set_of_cubes in games.values()
 )

2023/day6.py

@@ -1,22 +1,16 @@
-import operator
+import math
 import sys
-from functools import reduce
-
-lines = sys.stdin.read().splitlines()
 
 
 def extreme_times_to_beat(time: int, distance: int) -> tuple[int, int]:
-    import math
+    # formula (T = total time, D = target distance)
-
+    # - speed(t) = t,
-    # formula
+    # - distance(t) = (T - t) * speed(t)
-    # - distance = (T - t) * t
+    # - distance(t) > D
-    # - (T - t) * t >= D
+    #   <=> (T - t) * t > D
-    # - T * t - t^2 - D >= 0
+    #   <=> -t^2 + T * t - D >= 0
-
-    a = -1
-    b = time
-    c = -distance
 
+    a, b, c = -1, time, -distance
     d = b * b - 4 * a * c
 
     t1 = math.ceil(-(b - math.sqrt(d)) / (2 * a))
@@ -31,18 +25,17 @@ def extreme_times_to_beat(time: int, distance: int) -> tuple[int, int]:
     return t1, t2
 
 
+lines = sys.stdin.read().splitlines()
+
 # part 1
 times = list(map(int, lines[0].split()[1:]))
 distances = list(map(int, lines[1].split()[1:]))
-answer_1 = reduce(
+answer_1 = math.prod(
-    operator.mul,
+    t2 - t1 + 1
-    (
+    for t1, t2 in (
-        t2 - t1 + 1
+        extreme_times_to_beat(time, distance)
-        for t1, t2 in (
+        for time, distance in zip(times, distances)
-            extreme_times_to_beat(time, distance)
+    )
-            for time, distance in zip(times, distances)
-        )
-    ),
 )
 print(f"answer 1 is {answer_1}")