My Advent of Code solutions in Python.
kevinyap.ca/2019/12/going-fast-in-advent-of-code/
advent-of-code
python
Update solution for 2018/04
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-33
+16
-31
2018/day04.py
+16
-31
2018/day04.py
···
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import fileinput
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from collections import Counter, defaultdict
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from utils import parse_line
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from utils import parse_nums
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# Read problem input
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EVENTS = []
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for line in fileinput.input():
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data = parse_line(r'\[(\d+)-(\d+)-(\d+) (\d+):(\d+)\] (.+)', line)
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EVENTS.append(data)
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EVENTS.sort()
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EVENTS = sorted(parse_nums(line, negatives=False) for line in fileinput.input())
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# Process events
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SHIFTS = Counter()
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GUARDS = defaultdict(Counter)
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curr_id = None
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sleep = None
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sleep_min = None
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for year, month, date, hour, minute, action in EVENTS:
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if 'begins' in action:
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curr_id = int(action.split()[1][1:])
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for record in EVENTS:
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if len(record) == 6: # shift begins
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curr_id = int(record[-1])
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elif 'asleep' in action:
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sleep = hour, minute
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elif sleep_min is None: # falls asleep
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sleep_min = record[-1]
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elif 'wakes' in action:
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h, m = sleep
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SHIFTS[curr_id] += ((hour - h) % 24) * 60 + (minute - m)
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sleep = None
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else: # wakes up
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minute = record[-1]
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SHIFTS[curr_id] += minute - sleep_min
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for m in range(sleep_min, minute):
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GUARDS[curr_id][m] += 1
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for x in range(h * 60 + m, hour * 60 + minute):
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GUARDS[curr_id][x % 60] += 1
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sleep_min = None
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# Compute Part 1 answer
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guard_id = SHIFTS.most_common(1)[0][0]
···
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print "Strategy 1 checksum:", guard_id * minute
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# Compute Part 2 answer
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max_cnt = 0
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max_min = 0
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max_id = 0
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for guard_id, minutes in GUARDS.items():
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minute, count = minutes.most_common(1)[0]
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if count > max_cnt:
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max_cnt = count
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max_min = minute
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max_id = guard_id
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print "Strategy 2 checksum:", max_id * max_min
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guard_id, (minute, _) = max(((i, c.most_common(1)[0]) for i, c in GUARDS.items()), key=lambda x: x[1][1])
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print "Strategy 2 checksum:", guard_id * minute
+3
-2
2018/utils.py
+3
-2
2018/utils.py
···
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return ret
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def parse_nums(line):
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return [int(n) for n in re.findall(r'-?\d+', line)]
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def parse_nums(line, negatives=True):
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num_re = r'-?\d+' if negatives else r'\d+'
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return [int(n) for n in re.findall(num_re, line)]
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def new_table(val, width, height):