Solution to Problem 14 in Python

src/Year_2015/P14.py

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+# --- Day 14: Reindeer Olympics ---
+
+# This year is the Reindeer Olympics! Reindeer can fly at high speeds, but must
+# rest occasionally to recover their energy. Santa would like to know which of
+# his reindeer is fastest, and so he has them race.
+
+# Reindeer can only either be flying (always at their top speed) or resting
+# (not moving at all), and always spend whole seconds in either state.
+
+# For example, suppose you have the following Reindeer:
+
+#     Comet can fly 14 km/s for 10 seconds, but then must rest for 127 seconds.
+#     Dancer can fly 16 km/s for 11 seconds, but then must rest for 162 seconds.
+
+# After one second, Comet has gone 14 km, while Dancer has gone 16 km. After ten
+# seconds, Comet has gone 140 km, while Dancer has gone 160 km. On the eleventh
+# second, Comet begins resting (staying at 140 km), and Dancer continues on for
+# a total distance of 176 km. On the 12th second, both reindeer are resting.
+# They continue to rest until the 138th second, when Comet flies for another ten
+# seconds. On the 174th second, Dancer flies for another 11 seconds.
+
+# In this example, after the 1000th second, both reindeer are resting, and Comet
+# is in the lead at 1120 km (poor Dancer has only gotten 1056 km by that point).
+# So, in this situation, Comet would win (if the race ended at 1000 seconds).
+
+# Given the descriptions of each reindeer (in your puzzle input), after exactly
+# 2503 seconds, what distance has the winning reindeer traveled?
+
+import re
+
+with open("files/P14.txt") as f:
+    reindeers = [line for line in f.read().strip().split("\n")]
+
+reindeers_dict = {}
+for reindeer in reindeers:
+    reindeers_dict[reindeer.split()[0]] = list(
+        map(int, re.findall(r"\d+", reindeer))
+    )
+
+
+def part_1():
+    dist = {}
+    for reindeer, (kms, s1, s2) in reindeers_dict.items():
+        dist[reindeer] = (
+            2503 // (s1 + s2) * (kms * s1) + min(s1, 2503 % (s1 + s2)) * kms
+        )
+    print(f"The winning reindeer traveled {max(dist.values())} kms")
+
+
+# --- Part Two ---
+
+# Seeing how reindeer move in bursts, Santa decides he's not pleased with the
+# old scoring system.
+
+# Instead, at the end of each second, he awards one point to the reindeer
+# currently in the lead. (If there are multiple reindeer tied for the lead, they
+# each get one point.) He keeps the traditional 2503 second time limit, of
+# course, as doing otherwise would be entirely ridiculous.
+
+# Given the example reindeer from above, after the first second, Dancer is in
+# the lead and gets one point. He stays in the lead until several seconds into
+# Comet's second burst: after the 140th second, Comet pulls into the lead and
+# gets his first point. Of course, since Dancer had been in the lead for the 139
+# seconds before that, he has accumulated 139 points by the 140th second.
+
+# After the 1000th second, Dancer has accumulated 689 points, while poor Comet,
+# our old champion, only has 312. So, with the new scoring system, Dancer would
+# win (if the race ended at 1000 seconds).
+
+# Again given the descriptions of each reindeer (in your puzzle input), after
+# exactly 2503 seconds, how many points does the winning reindeer have?
+
+
+def part_2():
+    dist = {}
+    points = {reindeer: 0 for reindeer in reindeers_dict}
+    for sec in range(1, 2504):
+        for reindeer, (kms, s1, s2) in reindeers_dict.items():
+            dist[reindeer] = (
+                sec // (s1 + s2) * (kms * s1) + min(s1, sec % (s1 + s2)) * kms
+            )
+        maximum = max(dist.values())
+        for reindeer, value in dist.items():
+            if value == maximum:
+                points[reindeer] += 1
+    print(f"The winning reindeer has {max(points.values())} points")
+
+
+if __name__ == "__main__":
+    part_1()
+    part_2()