2015 day 14, part 2

2015/14/part1.py

@@ -20,4 +20,4 @@ for reindeer in reindeers:
     reindeer['distance'] = RACE_DURATION // cycle_duration * reindeer['speed'] * reindeer['duration']
     reindeer['distance'] += min(RACE_DURATION % cycle_duration, reindeer['duration']) * reindeer['speed']
 
-print(sorted(map(itemgetter('distance'), reindeers))[-1])
+print(max(map(itemgetter('distance'), reindeers)))

2015/14/part2.py

@@ -0,0 +1,49 @@
+#!/usr/bin/env python3
+from collections import namedtuple
+from math import ceil
+from operator import itemgetter
+import fileinput
+import re
+
+INPUT_RE = re.compile(r'^(?P<name>[A-Za-z]+) can fly (?P<speed>\d+) km/s for (?P<duration>\d+) seconds, but then must rest for (?P<cooldown>\d+) seconds\.$')
+RACE_DURATION = 2503
+
+reindeers = []
+for line in fileinput.input():
+    data = INPUT_RE.match(line).groupdict()
+    for k in ('speed', 'duration', 'cooldown'):
+        data[k] = int(data[k])
+    data.update(
+        distance=0,
+        score=0,
+        health=data['duration'],
+    )
+    reindeers.append(data)
+
+for _ in range(RACE_DURATION):
+    for reindeer in reindeers:
+        if reindeer['health'] < 0:  # Resting
+            reindeer['health'] += 1
+            if reindeer['health'] == 0:  # Done resting
+                reindeer['health'] = reindeer['duration']
+            continue
+
+        assert reindeer['health'] != 0
+        reindeer['health'] -= 1
+        reindeer['distance'] += reindeer['speed']
+        if reindeer['health'] == 0:  # Start resting
+            reindeer['health'] = -reindeer['cooldown']
+
+        
+    highest_distance = max(map(itemgetter('distance'), reindeers))
+    for reindeer in reindeers:
+        if reindeer['distance'] == highest_distance:
+            reindeer['score'] += 1
+
+# Compute one last time
+highest_distance = max(map(itemgetter('distance'), reindeers))
+for reindeer in reindeers:
+    if reindeer['distance'] == highest_distance:
+        reindeer['score'] += 1
+
+print(max(map(itemgetter('score'), reindeers)))