see ya, space cowgirl

toolkit.py

@@ -1,9 +1,11 @@
 import builtins
 import collections
+import functools
 import hashlib
-import itertools
 import importlib
+import itertools
 import math
+import operator
 import os
 import re
 import string
@@ -13,8 +15,7 @@ from pathlib import Path
 import requests
 
 
-def integers(line):
-    return [int(n) for n in re.findall(r'\d+', line)]
+product = functools.partial(functools.reduce, operator.mul)
 
 
 def lcm(a, b):
@@ -106,6 +107,7 @@ if __name__ == '__main__':
     data_file = Path(sys.argv[1]).with_suffix('.dat')
     ensure_data(data_file)
     builtins.df = data_file
+    builtins.text = data_file.read_text()
     builtins.string = string
     builtins.re = re
     rel = re.sub(r'.+(y\d+)/(p\d+).+', r'\1.\2', os.environ['FILE'])

y2015/p12.py

@@ -0,0 +1,19 @@
+import json
+
+
+def recurse(data, avoid=None):
+    type_ = type(data)
+    if type_ is int:
+        return data
+    elif type_ is str:
+        return 0
+    elif type_ is list:
+        return sum(recurse(el, avoid) for el in data)
+    elif type_ is dict:
+        if any(val == avoid for val in data.values()): return 0
+        return sum(recurse(value, avoid) for key, value in data.items())
+
+
+data = json.loads(df.read_text())
+ans1 = recurse(data)
+ans2 = recurse(data, 'red')

y2015/p13.py

@@ -0,0 +1,20 @@
+import collections
+import itertools
+
+
+happiness = collections.defaultdict(int)
+people = set()
+for line in df.read_text().splitlines():
+    A, verb, N, B = re.findall(r'([A-Z][a-z]+|gain|lose|\d+)', line)
+    happiness[A, B] = int(N) if verb == 'gain' else -int(N)
+    people.update({A, B})
+
+
+def calc(seq):
+    return sum(happiness[b, a] + happiness[b, c]
+        for a, b, c in zip(seq[-1:] + seq[:-1], seq, seq[1:] + seq[:1])
+    )
+
+
+ans1 = max(calc(combo) for combo in itertools.permutations(people))
+ans2 = max(calc(combo) for combo in itertools.permutations(people | {'me'}))

y2015/p14.py

@@ -0,0 +1,16 @@
+import collections
+import itertools
+
+
+reindeers = [
+    itertools.accumulate(itertools.cycle([speed] * act + [0] * rest))
+    for line in df.read_text().splitlines()
+    for speed, act, rest in [map(int, re.findall(r'\d+', line))]
+]
+
+
+traveled = [[next(rr) for _ in range(2503)] for rr in reindeers]
+transpose = list(zip(*traveled))
+ans1 = max(transpose[-1])
+points = [[d == max(dsts) for d in dsts] for dsts in transpose]
+ans2 = max(sum(pts) for pts in zip(*points))

y2015/p15.py

@@ -0,0 +1,19 @@
+from toolkit import product
+
+
+def combine(qtys):
+    return [max(0, sum(a * b for a, b in zip(qtys, vs))) for vs in zip(*data)]
+
+
+data = [
+    [int(n) for n in re.findall(r'-?\d+', ln)]
+    for ln in df.read_text().splitlines()
+]
+qtys = [
+    combine([A, B, C, 100 - A - B - C])
+    for A in range(101)
+    for B in range(101 - A)
+    for C in range(101 - A - B)
+]
+ans1 = max(product(combo[:-1]) for combo in qtys)
+ans2 = max(product(combo[:-1]) for combo in qtys if combo[-1] == 500)

y2015/p16.py

@@ -0,0 +1,24 @@
+known = {
+    'children': 3,
+    'cats': 7,
+    'samoyeds': 2,
+    'pomeranians': 3,
+    'akitas': 0,
+    'vizslas': 0,
+    'goldfish': 5,
+    'trees': 3,
+    'cars': 2,
+    'perfumes': 1,
+}
+for line in df.read_text().splitlines():
+    sue, N, *rest = re.findall(r'\w+', line)
+    stuff = {k: int(v) for k, v in zip(rest[::2], rest[1::2])}
+    if all(known[k] == stuff[k] for k in stuff):
+        ans1 = N
+    if all(
+        known[k] < stuff[k] if k in {'cats', 'trees'}
+        else known[k] > stuff[k] if k in {'pomeranians', 'goldfish'}
+        else known[k] == stuff[k]
+        for k in stuff):
+        ans2 = N
+

y2015/p17.py

@@ -0,0 +1,14 @@
+def recurse(pending, opts, chain=tuple()):
+    if pending == 0:
+        yield chain
+    else:
+        for i, opt in enumerate(opts):
+            yield from recurse(pending - opt, opts[i + 1:], chain + (opt,))
+
+
+ns = sorted([int(n) for n in df.read_text().splitlines()], reverse=True)
+opts = list(recurse(150, ns))
+ans1 = len(opts)
+
+min_n = min(map(len, opts))
+ans2 = sum(len(opt) == min_n for opt in opts)

y2015/p18.py

@@ -0,0 +1,24 @@
+def condition(x, y, on):
+    is_on = (x, y) in on
+    neighbours_on = sum(
+        (x + dx, y + dy) in on
+        for dx in [1, 0, -1] for dy in [1, 0, -1]
+        if dx or dy
+    )
+    return (is_on and neighbours_on in {2, 3}) or neighbours_on == 3
+
+
+on1 = {
+    (x, y)
+    for y, ln in enumerate(df.read_text().splitlines())
+    for x, ch in enumerate(ln)
+    if ch == '#'
+}
+on2 = set(on1)
+grid = {(x, y) for x in range(100) for y in range(100)}
+corners = {(0, 0), (0, 99), (99, 0), (99, 99)}
+for _ in range(100):
+    on1 = {(x, y) for x, y in grid if condition(x, y, on1)}
+    on2 = {(x, y) for x, y in grid if condition(x, y, on2)} | corners
+ans1 = len(on1)
+ans2 = len(on2)

y2015/p19.py

@@ -0,0 +1,19 @@
+pre, seq = text.strip().split('\n\n')
+formulas = re.findall(r'(\w+) => (\w+)', pre)
+
+
+ans1 = len({
+    seq[:match.start()] + seq[match.start():].replace(key, val, 1)
+    for key, val in formulas
+    for match in re.finditer(key, seq)
+})
+
+
+ops = formulas
+ans2 = 0
+while seq != 'e':
+    ans2 += 1
+    for k, v in ops:
+        if v in seq:
+            seq = seq.replace(v, k, 1)
+            break

y2015/p21.py

@@ -0,0 +1,50 @@
+import itertools
+
+
+def is_win(p_hp, p_atk, p_def, b_hp, b_atk, b_def):
+    while True:
+        b_hp -= max(1, p_atk - b_def)
+        if b_hp <= 0:
+            return True
+        p_hp -= max(1, b_atk - p_def)
+        if p_hp <= 0:
+            return False
+
+
+weapons = [
+    (8, 4, 0),
+    (10, 5, 0),
+    (25, 6, 0),
+    (40, 7, 0),
+    (74, 8, 0),
+]
+armors = [
+    (0, 0, 0),
+    (13, 0, 1),
+    (31, 0, 2),
+    (53, 0, 3),
+    (75, 0, 4),
+    (102, 0, 5),
+]
+rings = [
+    (0, 0, 0),
+    (0, 0, 0),
+    (25, 1, 0),
+    (50, 2, 0),
+    (100, 3, 0),
+    (20, 0, 1),
+    (40, 0, 2),
+    (80, 0, 3),
+]
+opts = [
+    [sum(vs) for vs in zip(*[w, a, r1, r2])]
+    for w, a in itertools.product(weapons, armors)
+    for r1, r2 in itertools.combinations(rings, 2)
+]
+p_hp = 100
+b_hp, b_atk, b_def = map(int, re.findall(r'(\d+)', text))
+wins = {True: set(), False: set()}
+for cost, p_atk, p_def in opts:
+    wins[is_win(p_hp, p_atk, p_def, b_hp, b_atk, b_def)].add(cost)
+ans1 = min(wins[True])
+ans2 = max(wins[False])