Solve 2018 day 16 and add function to download input

lib.py

@@ -11,20 +11,25 @@ INF = float("inf")
 fst = lambda l: l[0]
 snd = lambda l: l[1]
 
+
 def nth(n):
     return lambda l: l[n]
 
+
 def maps(f, xs):
     if isinstance(xs, list):
         return [maps(f, x) for x in xs]
     return f(xs)
 
+
 def mape(f, xs):
     return list(map(f, xs))
 
+
 def add2(a: tuple[int, int], b: tuple[int, int]) -> tuple[int, int]:
     return (a[0] + b[0], a[1] + b[1])
 
+
 class Grid2D:
     N = (-1, 0)
     E = (0, 1)
@@ -55,8 +60,7 @@ class Grid2D:
         c = Grid2D("d\nd")
         c.n_rows = self.n_rows
         c.n_cols = self.n_cols
-        c.grid = [[val for _ in range(c.n_cols)]
-                  for _ in range(self.n_rows)]
+        c.grid = [[val for _ in range(c.n_cols)] for _ in range(self.n_rows)]
         return c
 
     def rows(self) -> list[list[str]]:
@@ -64,8 +68,7 @@ class Grid2D:
 
     def cols(self) -> list[list[str]]:
         rows = self.rows()
-        return [[row[col_i] for row in rows]
-                for col_i in range(self.n_cols)]
+        return [[row[col_i] for row in rows] for col_i in range(self.n_cols)]
 
     def find(self, chars: str) -> list[tuple[int, int]]:
         return [c for c in self.all_coords() if self[c] in chars]
@@ -74,9 +77,11 @@ class Grid2D:
         return [c for c in self.all_coords() if self[c] not in chars]
 
     def all_coords(self) -> list[tuple[int, int]]:
-        return [(row_i, col_i)
-                for row_i in range(self.n_rows)
-                for col_i in range(self.n_cols)]
+        return [
+            (row_i, col_i)
+            for row_i in range(self.n_rows)
+            for col_i in range(self.n_cols)
+        ]
 
     def row_coords(self, row_i) -> list[tuple[int, int]]:
         assert row_i < self.n_rows, f"{row_i=} must be smaller than {self.n_rows=}"
@@ -94,10 +99,14 @@ class Grid2D:
         return self.contains(pos)
 
     def neighbors_ort(self, pos: tuple[int, int]) -> list[tuple[int, int]]:
-        return [add2(pos, off) for off in self.dirs_ort() if self.contains(add2(pos, off))]
+        return [
+            add2(pos, off) for off in self.dirs_ort() if self.contains(add2(pos, off))
+        ]
 
     def neighbors_vert(self, pos: tuple[int, int]) -> list[tuple[int, int]]:
-        return [add2(pos, off) for off in self.dirs_vert() if self.contains(add2(pos, off))]
+        return [
+            add2(pos, off) for off in self.dirs_vert() if self.contains(add2(pos, off))
+        ]
 
     def neighbors_adj(self, pos: tuple[int, int]) -> list[tuple[int, int]]:
         return self.neighbors_ort(pos) + self.neighbors_vert(pos)
@@ -119,6 +128,7 @@ class Grid2D:
         for r in self.rows():
             print(" ".join(map(str, r)))
 
+
 class Input:
     def __init__(self, text: str):
         if os.path.isfile(text):
@@ -141,6 +151,7 @@ class Input:
     def grid2(self) -> Grid2D:
         return Grid2D(self.text)
 
+
 def prime_factors(n):
     """
     Returns a list of prime factors for n.
@@ -163,6 +174,7 @@ def prime_factors(n):
         factors.append(rest)
     return factors
 
+
 def lcm(numbers: list[int]) -> int:
     fs = []
     for n in numbers:
@@ -173,6 +185,7 @@ def lcm(numbers: list[int]) -> int:
         s *= f
     return s
 
+
 def str_to_int(line: str) -> int:
     line = line.replace(" ", "")
     r = re.compile(r"(-?\d+)")
@@ -180,16 +193,20 @@ def str_to_int(line: str) -> int:
     (x,) = m
     return int(x)
 
+
 def str_to_ints(line: str) -> list[int]:
     r = re.compile(r"-?\d+")
     return list(map(int, r.findall(line)))
 
+
 def str_to_lines_no_empty(text: str) -> list[str]:
     return list(filter(lambda l: l.strip() != "", text.splitlines()))
 
+
 def str_to_lines(text: str) -> list[str]:
     return list(text.splitlines())
 
+
 def count_trailing_repeats(lst):
     count = 0
     for elem in reversed(lst):
@@ -199,6 +216,7 @@ def count_trailing_repeats(lst):
             count += 1
     return count
 
+
 class A_Star(object):
     def __init__(self, starts, is_goal, h, d, neighbors):
         """
@@ -221,12 +239,12 @@ class A_Star(object):
 
             for neighbor in neighbors(current):
                 tentative_g_score = g_score[current] + d(current, neighbor)
-                if neighbor not in g_score or \
-                   tentative_g_score < g_score[neighbor]:
+                if neighbor not in g_score or tentative_g_score < g_score[neighbor]:
                     g_score[neighbor] = tentative_g_score
                     f_score = g_score[neighbor] + h(neighbor)
                     heapq.heappush(open_set, (f_score, neighbor))
 
+
 def shoelace_area(corners):
     n = len(corners)
     area = 0
@@ -236,7 +254,25 @@ def shoelace_area(corners):
         area += (x1 * y2) - (x2 * y1)
     return abs(area) / 2.0
 
+
 def extract_year_and_date(scriptname) -> tuple[str, str]:
     r = re.compile(r"aoc(\d\d\d\d)/d(\d+).py")
     [(year, day)] = r.findall(scriptname)
     return (year, day)
+
+
+def get_data(filename):
+    path, file = os.path.split(filename)
+    year = path[-4:]
+    day = file.replace("d", "").replace(".py", "")
+    txt_file = f"d{day}.txt"
+
+    if os.path.isfile(txt_file):
+        with open(txt_file) as f:
+            return f.read()
+    else:
+        import subprocess
+        subprocess.call(["../get.py", year, day])
+        assert os.path.isfile(txt_file), "Could not download AoC file"
+        with open(txt_file) as f:
+            return f.read()