day 8

day08/input.txt

@@ -0,0 +1,50 @@
+...........g......................................
+......e.g......s.............R...........I........
+............g........................I............
+..b......Q....s.....................P.............
+.......e..T...................K...........P...F...
+.....g................U.............4.............
+.........b..........4..RU..................1.F....
+....a.....Q..........b........R..U...............1
+.S...T............s.............I.........f.......
+...A....T...............................I.........
+.....Qa............A.G...K...........P............
+...........................G................1.....
+...D...................................4.f........
+..................................................
+................k.......R....................t....
+.........T.e..............K........u.......t......
+....................A.............................
+......S....a.............F...........KG...........
+....D...h......k..................................
+..D...............k............................4..
+..............................................i...
+.........S..................d.....................
+......QU....S......s..d...G............i..........
+...........d....9...F.h...E.......................
+.................d....B...........................
+...h........................H.......t.............
+.........h.B..3.E.............H..r................
+.......E......B......2...5.....H..................
+.z...........9................................t...
+.....9...D........................................
+.....Z.......39..a................................
+..........3.............r.........................
+...............Er.............................7...
+.........................J...k.r.q.......i.8.p....
+.......................u...............H.p..q.....
+..............................i.u6........p.......
+....................................0.............
+...............3..J....P...0......................
+........................2j........................
+...............................j2B0...............
+................J..2...5.....6......p....8........
+............y.........................7...........
+..............5.........y...........6.............
+................................j.................
+.........................Y.J.....0................
+.........................................y........
+..................Z...uy...................q......
+.......z.........Z............Y.6.............8...
+z.........................Y..........7............
+....................Z...5..Y......................

day08/part1.py

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+from __future__ import annotations
+
+import argparse
+import collections
+import itertools
+import os.path
+
+import pytest
+
+import support
+
+INPUT_TXT = os.path.join(os.path.dirname(__file__), 'input.txt')
+
+
+def compute(s: str) -> int:
+    beacons: dict[str, list[tuple[int, int]]]
+    beacons = collections.defaultdict(list)
+
+    for y, line in enumerate(s.splitlines()):
+        for x, c in enumerate(line):
+            if c != '.':
+                beacons[c].append((x, y))
+
+    bx = range(0, len(s.splitlines()[0]))
+    by = range(0, len(s.splitlines()))
+
+    antinodes = set()
+    for nodes in beacons.values():
+        for (x1, y1), (x2, y2) in itertools.combinations(nodes, 2):
+            dx, dy = x2 - x1, y2 - y1
+            antinodes.add((x2 + dx, y2 + dy))
+            antinodes.add((x1 - dx, y1 - dy))
+
+    return len({(x, y) for x, y in antinodes if x in bx if y in by})
+
+
+INPUT_S = '''\
+............
+........0...
+.....0......
+.......0....
+....0.......
+......A.....
+............
+............
+........A...
+.........A..
+............
+............
+'''
+EXPECTED = 14
+
+
+@pytest.mark.parametrize(
+    ('input_s', 'expected'),
+    (
+        (INPUT_S, EXPECTED),
+    ),
+)
+def test(input_s: str, expected: int) -> None:
+    assert compute(input_s) == expected
+
+
+def main() -> int:
+    parser = argparse.ArgumentParser()
+    parser.add_argument('data_file', nargs='?', default=INPUT_TXT)
+    args = parser.parse_args()
+
+    with open(args.data_file) as f, support.timing():
+        print(compute(f.read()))
+
+    return 0
+
+
+if __name__ == '__main__':
+    raise SystemExit(main())

day08/part2.py

@@ -0,0 +1,86 @@
+from __future__ import annotations
+
+import argparse
+import collections
+import itertools
+import os.path
+
+import pytest
+
+import support
+
+INPUT_TXT = os.path.join(os.path.dirname(__file__), 'input.txt')
+
+
+def compute(s: str) -> int:
+    beacons: dict[str, list[tuple[int, int]]]
+    beacons = collections.defaultdict(list)
+
+    for y, line in enumerate(s.splitlines()):
+        for x, c in enumerate(line):
+            if c != '.':
+                beacons[c].append((x, y))
+
+    bx = range(0, len(s.splitlines()[0]))
+    by = range(0, len(s.splitlines()))
+
+    antinodes = set()
+    for nodes in beacons.values():
+        for (x1, y1), (x2, y2) in itertools.combinations(nodes, 2):
+            dx, dy = x2 - x1, y2 - y1
+
+            # positive
+            cx, cy = x2, y2
+            while cx in bx and cy in by:
+                antinodes.add((cx, cy))
+                cx, cy = cx + dx, cy + dy
+
+            # negative
+            cx, cy = x1, y1
+            while cx in bx and cy in by:
+                antinodes.add((cx, cy))
+                cx, cy = cx - dx, cy - dy
+
+    return len(antinodes)
+
+
+INPUT_S = '''\
+............
+........0...
+.....0......
+.......0....
+....0.......
+......A.....
+............
+............
+........A...
+.........A..
+............
+............
+'''
+EXPECTED = 34
+
+
+@pytest.mark.parametrize(
+    ('input_s', 'expected'),
+    (
+        (INPUT_S, EXPECTED),
+    ),
+)
+def test(input_s: str, expected: int) -> None:
+    assert compute(input_s) == expected
+
+
+def main() -> int:
+    parser = argparse.ArgumentParser()
+    parser.add_argument('data_file', nargs='?', default=INPUT_TXT)
+    args = parser.parse_args()
+
+    with open(args.data_file) as f, support.timing():
+        print(compute(f.read()))
+
+    return 0
+
+
+if __name__ == '__main__':
+    raise SystemExit(main())