Use abstract container types as type hints in function's parameters

Author: kwj

python/euler/bin/p0018.py

@@ -1,6 +1,6 @@
 # project euler: problem 18
 
-from collections.abc import Callable
+from collections.abc import Callable, Reversible, Sequence
 from functools import reduce
 from itertools import pairwise
 from operator import add
@@ -26,7 +26,7 @@
 # fmt: on
 
 
-def compute(fn: Callable[..., int], nums: list[list[int]]) -> str:
+def compute(fn: Callable[..., int], nums: Reversible[Sequence[int]]) -> str:
     return str(reduce(lambda x, y: list(map(add, map(fn, pairwise(x)), y)), reversed(nums))[0])
 
 

python/euler/bin/p0022.py

@@ -1,9 +1,10 @@
 # project euler: problem 22
 
+from collections.abc import Iterable
 from typing import IO
 
 
-def total_score(words: list[str]) -> int:
+def total_score(words: Iterable[str]) -> int:
     def score(word):
         return sum(ord(c) - (ord('A') - 1) for c in word)
 

python/euler/bin/p0024.py

@@ -1,5 +1,6 @@
 # project euler: problem 24
 
+from collections.abc import MutableSequence
 from math import factorial
 
 
@@ -14,7 +15,7 @@ def make_fact_tbl(num: int, depth: int) -> list[int]:
     return result
 
 
-def compute(nth: int, elm_lst: list[int], depth: int) -> str:
+def compute(nth: int, elm_lst: MutableSequence[int], depth: int) -> str:
     idx = nth - 1
     result = []
     for n in make_fact_tbl(len(elm_lst), depth):

python/euler/bin/p0031.py

@@ -1,7 +1,9 @@
 # project euler: problem 31
 
+from collections.abc import Iterable
 
-def compute(coins: list[int], target: int) -> str:
+
+def compute(coins: Iterable[int], target: int) -> str:
     tbl = [0] * (target + 1)
     tbl[0] = 1
 

python/euler/bin/p0033.py

@@ -32,13 +32,13 @@
 #
 # I only need to search in the case #1.
 
-from collections.abc import Iterator
+from collections.abc import Generator
 from functools import reduce
 from itertools import combinations
 from math import gcd
 
 
-def make_cands() -> Iterator[tuple[int, int]]:
+def make_cands() -> Generator[tuple[int, int], None, None]:
     # Note: The function check() assumes that a < b < c.
     #
     # The combination tuples which are generated by itertools.combinations() are emitted

python/euler/bin/p0037.py

@@ -3,19 +3,21 @@
 # candidate numbers: [2357][1379]*[37] (n >= 10)
 #                          ----------- lst
 
+from collections.abc import Iterable
+
 from euler.lib.prime import is_prime
 from euler.lib.util import num_of_digits
 
 
-def add_prefix_num(pre_lst: list[int], lst: list[int]) -> list[int]:
+def add_prefix_num(pre_lst: Iterable[int], lst: Iterable[int]) -> list[int]:
     return [p * (10 ** num_of_digits(n)) + n for p in pre_lst for n in lst]
 
 
-def make_next_lists(lst: list[int]) -> list[int]:
+def make_next_lists(lst: Iterable[int]) -> list[int]:
     return list(filter(is_prime, add_prefix_num([1, 3, 7, 9], lst)))
 
 
-def pickup_primes(lst: list[int]) -> list[int]:
+def pickup_primes(lst: Iterable[int]) -> list[int]:
     def is_truncable_prime(n: int) -> bool:
         if n == 0:
             return False

python/euler/bin/p0042.py

@@ -1,11 +1,12 @@
 # project euler: problem 42
 
+from collections.abc import Iterable
 from typing import IO
 
 from euler.lib.util import is_triangular
 
 
-def calc_scores(words: list[str]) -> list[int]:
+def calc_scores(words: Iterable[str]) -> list[int]:
     a_to_z = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ'
     tbl = dict(zip(a_to_z, range(1, len(a_to_z) + 1), strict=True))
 

python/euler/bin/p0050.py

@@ -1,12 +1,12 @@
 # project euler: problem 50
 
-from collections.abc import Iterator
+from collections.abc import Generator
 from itertools import dropwhile
 
 from euler.lib.prime import is_prime, prime_generator
 
 
-def cumsum_generator() -> Iterator[int]:
+def cumsum_generator() -> Generator[int, None, None]:
     acc = 0
     p_gen = prime_generator()
     while True:
@@ -17,7 +17,7 @@ def cumsum_generator() -> Iterator[int]:
 # Returns a cumulative sum list of prime numbers.
 #   [0, p1, p1+p2, p1+p2+p3, ..., p1+...+p{n-1}, p1+...+p{n-1}+p{n}]
 #     where sum(p1..p{n-1}) < limit and sum(p1..p{n}) >= limit
-def init_cumsum_lst(cs_gen: Iterator[int], limit: int) -> list[int]:
+def init_cumsum_lst(cs_gen: Generator[int, None, None], limit: int) -> list[int]:
     lst = [0]
     while lst[-1] < limit:
         lst.append(next(cs_gen))

python/euler/bin/p0051.py

@@ -33,6 +33,7 @@
 #
 # 4) There are at least same three numbers other than last digit.
 
+from collections.abc import Iterable, Sequence
 from functools import reduce
 from itertools import combinations, count
 
@@ -85,7 +86,7 @@ def flip_bits(pos_tpl: tuple[int, tuple[int, ...]]) -> tuple[int, list[int]]:
 
 # assemble_num(231, [0, 1, 1, 1, 0, 0], 7)
 #   --> 237771
-def assemble_num(i: int, pat: list[int], r: int) -> int:
+def assemble_num(i: int, pat: Iterable[int], r: int) -> int:
     lst = []
     for flag in pat:
         if flag == 0:
@@ -97,7 +98,7 @@ def assemble_num(i: int, pat: list[int], r: int) -> int:
     return reduce(lambda x, y: 10 * x + y, reversed(lst))
 
 
-def is_probable(i: int, pat: list[int], current_min: int) -> bool:
+def is_probable(i: int, pat: Sequence[int], current_min: int) -> bool:
     # Is MSB target digit to replace or not?
     if pat[-1] == 1:
         return assemble_num(i, pat, 1) < current_min
@@ -106,7 +107,7 @@ def is_probable(i: int, pat: list[int], current_min: int) -> bool:
 
 
 # Check all cases
-def find_prime(i: int, pat: list[int]) -> int | None:
+def find_prime(i: int, pat: Sequence[int]) -> int | None:
     # If MSB is target digit to replace, '0' is not applicable.
     start = 0
     if pat[-1] == 1:

python/euler/bin/p0054.py

@@ -30,11 +30,11 @@
 #         AH JH TH QH KH -> [9, 14, 13, 12, 11, 10]) - Royal Flush [9; 14; 13; 12; 11; 10]
 
 from collections import Counter
-from collections.abc import Iterator
+from collections.abc import Iterable, Iterator, Sequence
 from typing import IO
 
 
-def get_handrank(hand: list[str]) -> list[int]:
+def get_handrank(hand: Iterable[str]) -> list[int]:
     def rank_to_num(s: str) -> int:
         tbl = {
             '2': 2,
@@ -53,10 +53,10 @@ def rank_to_num(s: str) -> int:
         }
         return tbl[s]
 
-    def is_straight(lst: list[int]) -> bool:
+    def is_straight(lst: Sequence[int]) -> bool:
         return lst == list(range(lst[0], lst[0] - 5, -1))
 
-    def get_detail(h_info: list[tuple[int, int]]) -> list[int]:
+    def get_detail(h_info: Iterable[tuple[int, int]]) -> list[int]:
         detail, _ = zip(*h_info, strict=True)
         return list(detail)
 
@@ -121,7 +121,7 @@ def parse_data(fh: IO) -> Iterator[list[list[str]]]:
             [line.split(' ') for line in fh.read().splitlines()],
         )
 
-    def determine(lst: list[list[str]]) -> int:
+    def determine(lst: Sequence[Iterable[str]]) -> int:
         p1, p2 = get_handrank(lst[0]), get_handrank(lst[1])
         if p1 > p2:
             return 1
@@ -130,9 +130,9 @@ def determine(lst: list[list[str]]) -> int:
         else:
             return 0
 
-    hands_lst = parse_data(fh)
+    hands_it = parse_data(fh)
     p1 = p2 = draw = 0
-    for hands in hands_lst:
+    for hands in hands_it:
         match determine(hands):
             case 1:
                 p1 += 1