4 files changed, 14 insertions, 4 deletions
diff --git a/1.py b/1.py
index 2cc64a1..afd445d 100644
--- a/1.py
+++ b/1.py
@@ -1,5 +1,5 @@
-from utils import sliding_window
+from utils import open_day, sliding_window
 
-inp: list[int] = list(map(int, open('1.in')))
+inp: list[int] = list(map(int, open_day(1)))
 print(sum(s[0] < s[1] for s in sliding_window(inp, 2)))
 print(sum(s[0] < s[3] for s in sliding_window(inp, 4)))
diff --git a/2.py b/2.py
index 618cd86..dd33814 100644
--- a/2.py
+++ b/2.py
@@ -1,3 +1,5 @@
+from utils import open_day
+
 Command = tuple[str, int]
 
 def part1(commands: list[Command]) -> int:
@@ -23,6 +25,6 @@ def part2(commands: list[Command]) -> int:
                 depth += aim * X
     return pos * depth
 
-commands: list[Command] = [(c, int(q)) for c, q in (l.split() for l in open('2.in'))]
+commands: list[Command] = [(c, int(q)) for c, q in (l.split() for l in open_day(2))]
 print(part1(commands))
 print(part2(commands))
diff --git a/3.py b/3.py
index c4f645c..6e77680 100644
--- a/3.py
+++ b/3.py
@@ -1,3 +1,5 @@
+from utils import open_day
+
 Bits = tuple[bool, ...]
 Input = list[Bits]
 
@@ -25,7 +27,7 @@ def part2(nums: Input) -> int:
     co2: Bits = part2_impl(nums, True)
     return bits_to_int(oxygen) * bits_to_int(co2)
 
-inp: Input = [tuple(c == '1' for c in l.strip()) for l in open('3.in')]
+inp: Input = [tuple(c == '1' for c in l.strip()) for l in open_day(3)]
 
 print(part1(inp))
 print(part2(inp))
diff --git a/utils.py b/utils.py
index d322ed0..91b90ff 100644
--- a/utils.py
+++ b/utils.py
@@ -1,6 +1,7 @@
 from collections import deque
 from collections.abc import Iterable, Iterator, Generator
 from itertools import islice
+from sys import argv
 from typing import TypeVar
 
 T = TypeVar('T')
@@ -13,3 +14,8 @@ def sliding_window(iterable: Iterable[T], n: int) -> Generator[tuple[T, ...], No
     for x in it:
         window.append(x)
         yield tuple(window)
+
+def open_day(n: int):
+    if len(argv) == 2:
+        return open(argv[1])
+    return open(f'{n}.in')