Day 6 completed

Day5 part 2 still ongoing

day6/data.py

@@ -0,0 +1,13 @@
+from dataclasses import dataclass
+
+
+@dataclass
+class Race:
+    time: int
+    record: int
+
+    def length_for_button_press(self, duration: int) -> int:
+        length = 0
+        for i in range(duration, self.time):
+            length += duration
+        return length

day6/part1.py

@@ -0,0 +1,36 @@
+#!/usr/bin/env python3.11
+import math
+import re
+from typing import List
+
+from data import Race
+
+
+def extract(input_file: str) -> List[Race]:
+    races = []
+    with open(input_file) as input:
+        times = re.match("Time:((?:\s+\d+)+)", input.readline())
+        times = list(map(int, re.split("\s+", times.group(1).lstrip())))
+        distances = re.match("Distance:((?:\s+\d+)+)", input.readline())
+        distances = list(map(int, re.split("\s+", distances.group(1).lstrip())))
+        if len(times) == len(distances):
+            for idx in range(len(times)):
+                r = Race(time=times[idx], record=distances[idx])
+                races.append(r)
+        else:
+            raise Exception("Times and Distances are not the same length")
+    return races
+
+
+input_file = "input.txt"
+races = extract(input_file)
+record_beatings = [0 for r in races]
+
+
+for idx, race in enumerate(races):
+    lengths = []
+    for i in range(race.time):
+        lengths.append(race.length_for_button_press(i))
+    record_beatings[idx] = len(list(filter(lambda length: length > race.record, lengths)))
+print(record_beatings)
+print(math.prod(record_beatings))

day6/part2.py

@@ -0,0 +1,43 @@
+#!/usr/bin/env python3.11
+import re
+from data import Race
+
+
+def extract(input_file: str) -> Race:
+    with open(input_file) as input:
+        time = re.match("Time: ((?:\s+\d+)+)", input.readline())
+        time = int(re.sub("\s+", "", time.group(1)))
+        distance = re.match("Distance: ((?:\s+\d+)+)", input.readline())
+        distance = int(re.sub("\s+", "", distance.group(1)))
+        return Race(time=time, record=distance)
+
+
+def find_boundary(race: Race, start: int, end: int, nrange: int, reverse: bool = False) -> int:
+    print(race, start, end, nrange, reverse)
+    step = nrange if not reverse else -nrange
+    if nrange == 1:
+        for i in range(start, end + 1, step):
+            if race.length_for_button_press(i) > race.record:
+                return i
+    boundary = start
+    for i in range(start, end + 1, step):
+        boundary = i
+        if race.length_for_button_press(i) > race.record:
+            return find_boundary(race, boundary - step, boundary, int(nrange / 10), reverse)
+
+
+input_file = "input.txt"
+race = extract(input_file)
+
+start = end = 0
+step = 1
+while step < race.time:
+    step *= 10
+step /= 10
+print(step)
+start = find_boundary(race, 0, race.time, int(step))
+print(start)
+end = find_boundary(race, race.time, start, int(step), True)
+
+
+print(end - start + 1)