diff --git a/2022/day1.py b/2022/day1.py
index 47da67a..4dc115c 100644
--- a/2022/day1.py
+++ b/2022/day1.py
@@ -1,5 +1,3 @@
-# -*- encoding: utf-8 -*-
-
 import sys
 
 blocks = sys.stdin.read().split("\n\n")
diff --git a/2022/day10.py b/2022/day10.py
index 5519cf2..73470c6 100644
--- a/2022/day10.py
+++ b/2022/day10.py
@@ -1,5 +1,3 @@
-# -*- encoding: utf-8 -*-
-
 import sys
 
 lines = sys.stdin.read().splitlines()
diff --git a/2022/day11.py b/2022/day11.py
index ed439cd..5c2efd9 100644
--- a/2022/day11.py
+++ b/2022/day11.py
@@ -1,5 +1,3 @@
-# -*- encoding: utf-8 -*-
-
 import copy
 import sys
 from functools import reduce
@@ -7,7 +5,6 @@ from typing import Callable, Final, Mapping, Sequence
 
 
 class Monkey:
-
     id: Final[int]
     items: Final[Sequence[int]]
     worry_fn: Final[Callable[[int], int]]
@@ -97,8 +94,7 @@ def run(
     # number of inspects
     inspects = {monkey: 0 for monkey in monkeys}
 
-    for round in range(n_rounds):
-
+    for _ in range(n_rounds):
         for monkey in monkeys:
             for item in items[monkey]:
                 inspects[monkey] += 1
diff --git a/2022/day12.py b/2022/day12.py
index e03bb54..66d1752 100644
--- a/2022/day12.py
+++ b/2022/day12.py
@@ -1,5 +1,3 @@
-# -*- encoding: utf-8 -*-
-
 import heapq
 import sys
 from typing import Callable, Iterator, TypeVar
@@ -44,7 +42,6 @@ def dijkstra(
         visited.add(current)
 
         for neighbor in neighbors(current):
-
             if neighbor in visited:
                 continue
 
@@ -60,7 +57,6 @@ def dijkstra(
 
 
 def make_path(parents: dict[Node, Node], start: Node, end: Node) -> list[Node] | None:
-
     if end not in parents:
         return None
 
@@ -109,7 +105,6 @@ def neighbors(
         (c_row, c_col - 1),
         (c_row, c_col + 1),
     ):
-
         if not (n_row >= 0 and n_row < n_rows and n_col >= 0 and n_col < n_cols):
             continue
 
diff --git a/2022/day13.py b/2022/day13.py
index d717412..c9d2361 100644
--- a/2022/day13.py
+++ b/2022/day13.py
@@ -1,27 +1,27 @@
-# -*- encoding: utf-8 -*-
-
 import json
 import sys
 from functools import cmp_to_key
+from typing import TypeAlias, cast
 
 blocks = sys.stdin.read().strip().split("\n\n")
 
 pairs = [tuple(json.loads(p) for p in block.split("\n")) for block in blocks]
 
+Packet: TypeAlias = list[int | list["Packet"]]
 
-def compare(lhs: list[int | list], rhs: list[int | list]) -> int:
 
+def compare(lhs: Packet, rhs: Packet) -> int:
     for lhs_a, rhs_a in zip(lhs, rhs):
         if isinstance(lhs_a, int) and isinstance(rhs_a, int):
             if lhs_a != rhs_a:
                 return rhs_a - lhs_a
         else:
             if not isinstance(lhs_a, list):
-                lhs_a = [lhs_a]
+                lhs_a = [lhs_a]  # type: ignore
             elif not isinstance(rhs_a, list):
-                rhs_a = [rhs_a]
+                rhs_a = [rhs_a]  # type: ignore
             assert isinstance(rhs_a, list) and isinstance(lhs_a, list)
-            r = compare(lhs_a, rhs_a)
+            r = compare(cast(Packet, lhs_a), cast(Packet, rhs_a))
             if r != 0:
                 return r
 
diff --git a/2022/day14.py b/2022/day14.py
index 829893a..17d937c 100644
--- a/2022/day14.py
+++ b/2022/day14.py
@@ -1,7 +1,4 @@
-# -*- encoding: utf-8 -*-
-
 import sys
-from collections import defaultdict
 from enum import Enum, auto
 from typing import Callable, cast
 
@@ -23,10 +20,10 @@ def print_blocks(blocks: dict[tuple[int, int], Cell]):
         blocks: Set of blocks to print.
     """
     x_min, y_min, x_max, y_max = (
-        min(x for x, y in blocks),
+        min(x for x, _ in blocks),
         0,
-        max(x for x, y in blocks),
-        max(y for x, y in blocks),
+        max(x for x, _ in blocks),
+        max(y for _, y in blocks),
     )
 
     for y in range(y_min, y_max + 1):
@@ -56,13 +53,12 @@ def flow(
         The input blocks.
     """
 
-    y_max = max(y for x, y in blocks)
+    y_max = max(y for _, y in blocks)
 
     while True:
         x, y = 500, 0
 
         while y <= y_max:
-
             moved = False
             for cx, cy in ((x, y + 1), (x - 1, y + 1), (x + 1, y + 1)):
                 if (cx, cy) not in blocks and fill_fn(cx, cy) == Cell.AIR:
@@ -117,10 +113,10 @@ print_blocks(blocks)
 print()
 
 x_min, y_min, x_max, y_max = (
-    min(x for x, y in blocks),
+    min(x for x, _ in blocks),
     0,
-    max(x for x, y in blocks),
-    max(y for x, y in blocks),
+    max(x for x, _ in blocks),
+    max(y for _, y in blocks),
 )
 
 # === part 1 ===
diff --git a/2022/day15.py b/2022/day15.py
index 6ee3ffa..fd0fb0d 100644
--- a/2022/day15.py
+++ b/2022/day15.py
@@ -1,5 +1,3 @@
-# -*- encoding: utf-8 -*-
-
 import sys
 
 import numpy as np
@@ -7,7 +5,6 @@ import parse
 
 
 def part1(sensor_to_beacon: dict[tuple[int, int], tuple[int, int]], row: int) -> int:
-
     no_beacons_row_l: list[np.ndarray] = []
 
     for (sx, sy), (bx, by) in sensor_to_beacon.items():
@@ -37,7 +34,7 @@ def part2_intervals(
                 its.append((max(0, sx - dx), min(sx + dx, xy_max)))
 
         its = sorted(its)
-        s, e = its[0]
+        _, e = its[0]
 
         for si, ei in its[1:]:
             if si > e + 1:
diff --git a/2022/day16.py b/2022/day16.py
index 9af5a2c..055ed25 100644
--- a/2022/day16.py
+++ b/2022/day16.py
@@ -1,5 +1,3 @@
-# -*- encoding: utf-8 -*-
-
 from __future__ import annotations
 
 import heapq
@@ -69,7 +67,6 @@ def part_1(
     distances: dict[tuple[Pipe, Pipe], int],
     relevant_pipes: FrozenSet[Pipe],
 ):
-
     node_at_times: dict[int, dict[Pipe, dict[FrozenSet[Pipe], int]]] = defaultdict(
         lambda: defaultdict(lambda: defaultdict(lambda: 0))
     )
@@ -79,7 +76,6 @@ def part_1(
         for c_pipe, nodes in node_at_times[time].items():
             for flowing, flow in nodes.items():
                 for target in relevant_pipes:
-
                     distance = distances[c_pipe, target] + 1
                     if time + distance >= max_time or target in flowing:
                         continue
diff --git a/2022/day17.py b/2022/day17.py
index 200ed99..6f02c26 100644
--- a/2022/day17.py
+++ b/2022/day17.py
@@ -1,5 +1,3 @@
-# -*- encoding: utf-8 -*-
-
 import sys
 from typing import Sequence, TypeVar
 
@@ -49,7 +47,6 @@ def build_tower(
     early_stop: bool = False,
     init: np.ndarray = np.ones(WIDTH, dtype=bool),
 ) -> tuple[np.ndarray, int, int, dict[int, int]]:
-
     tower = EMPTY_BLOCKS.copy()
     tower[0, :] = init
 
@@ -59,7 +56,6 @@ def build_tower(
     rock_count = 0
 
     for rock_count in range(n_rocks):
-
         if early_stop:
             if i_rock == 0 and (i_rock, i_jet) in done_at:
                 break
@@ -75,7 +71,6 @@ def build_tower(
             tower = np.concatenate([tower, EMPTY_BLOCKS], axis=0)
 
         while True:
-
             jet, i_jet = next_cycle(jets, i_jet)
 
             dx = 0
diff --git a/2022/day18.py b/2022/day18.py
index 96aabf5..9feff8b 100644
--- a/2022/day18.py
+++ b/2022/day18.py
@@ -1,5 +1,3 @@
-# -*- encoding: utf-8 -*-
-
 import sys
 from typing import FrozenSet
 
diff --git a/2022/day19.py b/2022/day19.py
index 0a264b5..cd7860c 100644
--- a/2022/day19.py
+++ b/2022/day19.py
@@ -1,5 +1,3 @@
-# -*- encoding: utf-8 -*-
-
 import sys
 from typing import Literal
 
@@ -88,7 +86,6 @@ for line in lines:
 
 
 def run(blueprint: dict[Reagent, dict[Reagent, int]], max_time: int) -> int:
-
     # since we can only build one robot per time, we do not need more than X robots
     # of type K where X is the maximum number of K required among all robots, e.g.,
     # in the first toy blueprint, we need at most 4 ore robots, 14 clay ones and 7
@@ -100,7 +97,6 @@ def run(blueprint: dict[Reagent, dict[Reagent, int]], max_time: int) -> int:
     state_after_t: dict[int, set[State]] = {0: [State()]}
 
     for t in range(1, max_time + 1):
-
         # list of new states at the end of step t that we are going to prune later
         states_for_t: set[State] = set()
 
diff --git a/2022/day2.py b/2022/day2.py
index 0851812..4d23c7c 100644
--- a/2022/day2.py
+++ b/2022/day2.py
@@ -1,5 +1,3 @@
-# -*- encoding: utf-8 -*-
-
 import sys
 
 
@@ -49,7 +47,7 @@ lines = sys.stdin.readlines()
 values = [(ord(row[0]) - ord("A"), ord(row[2]) - ord("X")) for row in lines]
 
 # part 1 - 13526
-print(f"score 1 is {sum(score_1(*v) for v in values)}")
+print(f"answer 1 is {sum(score_1(*v) for v in values)}")
 
 # part 2 - 14204
-print(f"score 2 is {sum(score_2(*v) for v in values)}")
+print(f"answer 2 is {sum(score_2(*v) for v in values)}")
diff --git a/2022/day20.py b/2022/day20.py
index a8ed796..5448d0a 100644
--- a/2022/day20.py
+++ b/2022/day20.py
@@ -1,5 +1,3 @@
-# -*- encoding: utf-8 -*-
-
 from __future__ import annotations
 
 import sys
@@ -21,7 +19,6 @@ class Number:
 
 
 def decrypt(numbers: list[Number], key: int, rounds: int) -> int:
-
     numbers = numbers.copy()
     original = numbers.copy()
 
diff --git a/2022/day21.py b/2022/day21.py
index 6758bca..c5b3736 100644
--- a/2022/day21.py
+++ b/2022/day21.py
@@ -1,5 +1,3 @@
-# -*- encoding: utf-8 -*-
-
 import operator
 import sys
 from typing import Callable
diff --git a/2022/day22.py b/2022/day22.py
index f43d477..571f314 100644
--- a/2022/day22.py
+++ b/2022/day22.py
@@ -1,5 +1,3 @@
-# -*- encoding: utf-8 -*-
-
 import re
 import sys
 from typing import Callable
@@ -126,7 +124,6 @@ def wrap_part_2(y0: int, x0: int, r0: str) -> tuple[int, int, str]:
 
 
 def run(wrap: Callable[[int, int, str], tuple[int, int, str]]) -> tuple[int, int, str]:
-
     y0 = 0
     x0 = np.where(board[0] == EMPTY)[0][0]
     r0 = "E"
diff --git a/2022/day23.py b/2022/day23.py
index 02c9235..902c20b 100644
--- a/2022/day23.py
+++ b/2022/day23.py
@@ -1,5 +1,3 @@
-# -*- encoding: utf-8 -*-
-
 import itertools
 import sys
 from collections import defaultdict
@@ -41,7 +39,7 @@ def round(
     directions: Directions,
 ):
     to_move: dict[tuple[int, int], list[tuple[int, int]]] = defaultdict(lambda: [])
-    for (y, x) in positions:
+    for y, x in positions:
         elves = {
             (dy, dx): (y + dy, x + dx) in positions
             for dy, dx in itertools.product((-1, 0, 1), (-1, 0, 1))
diff --git a/2022/day24.py b/2022/day24.py
index 975f178..6ea76b9 100644
--- a/2022/day24.py
+++ b/2022/day24.py
@@ -1,5 +1,3 @@
-# -*- encoding: utf-8 -*-
-
 import heapq
 import math
 import sys
diff --git a/2022/day25.py b/2022/day25.py
index 553141a..4327247 100644
--- a/2022/day25.py
+++ b/2022/day25.py
@@ -1,5 +1,3 @@
-# -*- encoding: utf-8 -*-
-
 import sys
 
 lines = sys.stdin.read().splitlines()
diff --git a/2022/day3.py b/2022/day3.py
index eda40a1..b7740ed 100644
--- a/2022/day3.py
+++ b/2022/day3.py
@@ -1,5 +1,3 @@
-# -*- encoding: utf-8 -*-
-
 import string
 import sys
 
@@ -13,7 +11,7 @@ priorities = {c: i + 1 for i, c in enumerate(string.ascii_letters)}
 
 # part 1
 part1 = sum(priorities[c] for p1, p2 in parts for c in p1.intersection(p2))
-print(f"score 1 is {part1}")
+print(f"answer 1 is {part1}")
 
 # part 2
 n_per_group = 3
@@ -22,4 +20,4 @@ part2 = sum(
     for i in range(0, len(lines), n_per_group)
     for c in set(lines[i]).intersection(*lines[i + 1 : i + n_per_group])
 )
-print(f"score 2 is {part2}")
+print(f"answer 2 is {part2}")
diff --git a/2022/day4.py b/2022/day4.py
index efc98b3..bf6aae1 100644
--- a/2022/day4.py
+++ b/2022/day4.py
@@ -1,5 +1,3 @@
-# -*- encoding: utf-8 -*-
-
 import sys
 
 lines = [line.strip() for line in sys.stdin.readlines()]
@@ -12,8 +10,8 @@ def make_range(value: str) -> set[int]:
 
 sections = [tuple(make_range(part) for part in line.split(",")) for line in lines]
 
-score_1 = sum(s1.issubset(s2) or s2.issubset(s1) for s1, s2 in sections)
-print(f"score 1 is {score_1}")
+answer_1 = sum(s1.issubset(s2) or s2.issubset(s1) for s1, s2 in sections)
+print(f"answer 1 is {answer_1}")
 
-score_2 = sum(bool(s1.intersection(s2)) for s1, s2 in sections)
-print(f"score 1 is {score_2}")
+answer_2 = sum(bool(s1.intersection(s2)) for s1, s2 in sections)
+print(f"answer 1 is {answer_2}")
diff --git a/2022/day5.py b/2022/day5.py
index 0e53a44..04ba94f 100644
--- a/2022/day5.py
+++ b/2022/day5.py
@@ -1,5 +1,3 @@
-# -*- encoding: utf-8 -*-
-
 import copy
 import sys
 
diff --git a/2022/day6.py b/2022/day6.py
index abc67ad..086f33e 100644
--- a/2022/day6.py
+++ b/2022/day6.py
@@ -1,5 +1,3 @@
-# -*- encoding: utf-8 -*-
-
 import sys
 
 
diff --git a/2022/day7.py b/2022/day7.py
index 128a300..c95e1b9 100644
--- a/2022/day7.py
+++ b/2022/day7.py
@@ -1,5 +1,3 @@
-# -*- encoding: utf-8 -*-
-
 import sys
 from pathlib import Path
 
diff --git a/2022/day8.py b/2022/day8.py
index bc02123..ee75ede 100644
--- a/2022/day8.py
+++ b/2022/day8.py
@@ -1,8 +1,7 @@
-# -*- encoding: utf-8 -*-
-
 import sys
 
 import numpy as np
+from numpy.typing import NDArray
 
 lines = sys.stdin.read().splitlines()
 
@@ -27,7 +26,7 @@ answer_1 = (highest_trees.min(axis=2) < trees).sum()
 print(f"answer 1 is {answer_1}")
 
 
-def viewing_distance(row_of_trees: np.ndarray, value: int) -> int:
+def viewing_distance(row_of_trees: NDArray[np.int_], value: int) -> int:
     w = np.where(row_of_trees >= value)[0]
 
     if not w.size:
diff --git a/2022/day9.py b/2022/day9.py
index cd84ffb..f81ec93 100644
--- a/2022/day9.py
+++ b/2022/day9.py
@@ -1,12 +1,9 @@
-# -*- encoding: utf-8 -*-
-
 import sys
 
 import numpy as np
 
 
 def move(head: tuple[int, int], command: str) -> tuple[int, int]:
-
     h_col, h_row = head
 
     if command == "L":
@@ -22,7 +19,6 @@ def move(head: tuple[int, int], command: str) -> tuple[int, int]:
 
 
 def follow(head: tuple[int, int], tail: tuple[int, int]) -> tuple[int, int]:
-
     h_col, h_row = head
     t_col, t_row = tail
 
@@ -33,8 +29,7 @@ def follow(head: tuple[int, int], tail: tuple[int, int]) -> tuple[int, int]:
 
 
 def run(commands: list[str], n_blocks: int) -> list[tuple[int, int]]:
-
-    blocks = [(0, 0) for _ in range(n_blocks)]
+    blocks: list[tuple[int, int]] = [(0, 0) for _ in range(n_blocks)]
     visited = [blocks[-1]]
 
     for command in commands: