8 files changed, 120 insertions, 56 deletions

diff --git a/aoc/datastructures.py b/aoc/datastructures.py
new file mode 100644
index 0000000..c49f564
--- /dev/null
+++ b/aoc/datastructures.py
@@ -0,0 +1,27 @@
+# -*- coding: utf-8 -*-
+from collections import namedtuple
+
+
+class Coordinate(namedtuple("Coordinate", ["x", "y"])):
+    def __sub__(self, other: "Coordinate"):
+        return Coordinate(self.x - other.x, self.y - other.y)
+
+    def __add__(self, other: "Coordinate"):
+        return Coordinate(self.x + other.x, self.y + other.y)
+
+    def manhattan_distance(self, other: "Coordinate"):
+        return abs(self.x - other.x) + abs(self.y - other.y)
+
+    @property
+    def polarity_x(self):
+        try:
+            return abs(self.x) / self.x
+        except ZeroDivisionError:
+            return 0
+
+    @property
+    def polarity_y(self):
+        try:
+            return abs(self.y) / self.y
+        except ZeroDivisionError:
+            return 0
diff --git a/aoc/decorators.py b/aoc/decorators.py
new file mode 100644
index 0000000..a31993a
--- /dev/null
+++ b/aoc/decorators.py
@@ -0,0 +1,17 @@
+# -*- coding: utf-8 -*-
+from functools import wraps
+from typing import Iterator, TypeVar, Callable
+
+T = TypeVar("T")
+
+
+def infinite_generator(func: Callable[[...], Iterator[T]]):
+    @wraps(func)
+    def wrapper(*args, **kwargs):
+        items = list(func(*args, **kwargs))
+
+        while True:
+            for item in items:
+                yield item
+
+    return wrapper
diff --git a/day14/__init__.py b/day14/__init__.py
index 44107de..8869c79 100644
--- a/day14/__init__.py
+++ b/day14/__init__.py
@@ -4,8 +4,7 @@ from functools import lru_cache
 from typing import Tuple, Iterator, Set, Any, Optional
 
 from aoc import BaseAssignment
-
-Coordinate = Tuple[int, int]
+from aoc.datastructures import Coordinate
 
 
 class Assignment(BaseAssignment, ABC):
diff --git a/day15/__init__.py b/day15/__init__.py
index 5885f37..38bef35 100644
--- a/day15/__init__.py
+++ b/day15/__init__.py
@@ -1,17 +1,12 @@
 # -*- coding: utf-8 -*-
 import re
 from abc import ABC
-from collections import namedtuple
 from dataclasses import dataclass, field
-from typing import Tuple, Iterator, Any, Set, Union
-from typing import Tuple, Iterator, Any, Set, List
+from typing import Union
+from typing import Tuple, Iterator, Set, List
 
 from aoc import BaseAssignment
-
-
-class Coordinate(namedtuple("Coordinate", ["x", "y"])):
-    def distance(self, other: "Coordinate"):
-        return abs(self.x - other.x) + abs(self.y - other.y)
+from aoc.datastructures import Coordinate
 
 
 @dataclass
@@ -24,10 +19,10 @@ class Sensor:
         return hash(self.coordinate)
 
     def __post_init__(self):
-        self.radius = self.coordinate.distance(self.nearest)
+        self.radius = self.coordinate.manhattan_distance(self.nearest)
 
     def within_radius(self, coordinate: Coordinate) -> bool:
-        distance = self.coordinate.distance(coordinate)
+        distance = self.coordinate.manhattan_distance(coordinate)
         return distance <= self.radius
 
     def x_coordinates_within_radius_at(self, y: int, map: "Map") -> Union[range, list]:
diff --git a/day17/__init__.py b/day17/__init__.py
new file mode 100644
index 0000000..41b25dc
--- /dev/null
+++ b/day17/__init__.py
@@ -0,0 +1,42 @@
+# -*- coding: utf-8 -*-
+from abc import ABC
+from dataclasses import dataclass
+from typing import Iterator
+
+from aoc import BaseAssignment
+from aoc.datastructures import Coordinate
+from aoc.decorators import infinite_generator
+
+
+@dataclass
+class Block:
+    origin: Coordinate
+
+
+class Assignment(BaseAssignment[int, str], ABC):
+    @infinite_generator
+    def infinite_moves(self, item: str) -> str:
+        return item
+
+    def infinite_blocks(self):
+        pass
+
+
+class AssignmentOne(Assignment):
+    example_result = 1
+
+    def run(self, input: Iterator[str]):
+        i = 0
+
+        moves = self.infinite_moves(input)
+
+        for move in self.infinite_moves(next(input)):
+            i += 1
+            print(move)
+
+            if i == 100:
+                break
+
+
+class AssignmentTwo(Assignment):
+    pass
diff --git a/day17/example.txt b/day17/example.txt
new file mode 100644
index 0000000..97a1aa1
--- /dev/null
+++ b/day17/example.txt
@@ -0,0 +1 @@
+>>><<><>><<<>><>>><<<>>><<<><<<>><>><<>>
diff --git a/day17/input.txt b/day17/input.txt
new file mode 100644
index 0000000..3edbacf
--- /dev/null
+++ b/day17/input.txt
@@ -0,0 +1 @@
+>><<<<><><<>><>><<><<<>><>><<>><>><<>>><<<<>>>><<<<><>><><<>>>><><<<>>>><>><<><<<<>>><<<<>>>><<<>>><>>><>>>><<>>><<<>>><<<>><<>><<<>>><>>>><<<>><<<>>>><>>><><<>><<<><>>>><<<>>>><<>><<>>>><>><<<><<><<<<><<><<<>>>><<<>><<<<>><<<>><<<>><<<<>>>><<<>>>><<<>>>><<>>>><<<>><<<<><<<><>>>><<>>><<<<>><><>>>><<<<><<<<>>><<<>>><<<>><<<<>>>><<<>>>><<<<>>>><<<><<<>><<<>>><<<>>>><><<>><<><<<><>>><<<<>><<<>>><<>>>><><>>><>>>><>><>>>><<<<><<>>><<<<>><<<><<<<>>><<>>>><>>><<<>>><>><<>>>><<<><>>>><<>>><>><><<<<><<<>><<<<>><<<<><>>>><<><<>>><<>><>><>>><<><>>><<<<>>><>>>><<<>><>>>><<<<>>>><>>><>><>>><<>>><<>>><<<<>>>><<<<><<<<>><<>>><><<<><>><>>><<<>>><<<>><<>>><<<><<>>>><<<>>><<<>><><<>>><<<>><<<>><<<<>><><<>><<<<><<>>>><<<>>>><<<<><>>>><><<<>>>><<<<>>><>><<>><<<<><<<<>>>><<<>>><<<>>><><<>>><<>>>><<<>>><<>>>><<<>>><<<<><<<><<><<>><>>>><><<<>>>><<<<>>><<<>><<<<>>>><<>><<>>><>>><<>><>><<<>>><>>>><<>>>><<<>>>><>>>><<<>><<<<><<<<>>><>>>><><>>>><<<<><<<<><>><<<>><<<>>><<<<><<<><<<>>>><<><<>>>><>>>><<<>>>><>>><<<<>>><><<>>><<<>>><<>><>><>>>><<><<<<><<>>><><<<<>>>><><>><<>><<<><<<<>><<<<>><<<>>>><><>><<>>><<>>><<<<>>><<>>><<>><>>>><<<<>>><<<<><<<<>>>><<<>>><<>>>><<<<><>>><<<<><<<<>>><>>><<<<><>><<<<>>><<<<>>><<<<>>><<<>>><>>>><<<<>>><><<<<><>>>><<<<>><>><<<>>>><<<><>><<>><>>>><<><<<>>>><>><<>>>><<<>>><<<>>>><<>>><<>><<<>>>><<<><<<><<<>><<<>>><>>><<<<>>><<>><>>><<<<>>><>><<<>>><>><<<<>>>><><<<><<>>><>>><>>>><<>><<<<>>><<<><<<<>>>><><>>>><<<<>>><<<<><<><<<><<<<><<<<>>><>>><<>>><<<<><<><<<><<<<><<<<><>>><<<>>>><<<>>><>><>><<<<>>>><<<<>>>><>>><<>>><<>>>><<<<>>>><<<<>><<<<>><<><<<<>>>><<>>>><<>><<<<><>>>><<<<>>><<>>><<>>><>><>>><>>><<<<>>><<<<>><<<<>><<<<>><<<>><<>><>><>>><<<><<><<>>>><>>><<<>>><<<>>><<>>>><><<<<>>>><<>>><<<<>>><><<>>>><<>>><<>>>><<>>>><<><>>><<<<>>>><<>>>><<<<><<<>>><<<>>>><<<<>>><<<>><<<<>>><<<>>><<<>><<<<><<<<><>>><>>><<<<><<<<><<<<><<<<>>><<<<>><<>><>><>>><<<<>>>><>>>><<<>><>>><>>>><<<>><<>>>><<<<>><<<><<>><<<>><><><<<><<<>>><>>>><<>><>>><>>>><>>>><<<<>>>><<<<>>>><<<<>>><<>><<>>><<>><<><>><<<>>>><>>><>>><<<>><><<<<>>><<<><<<>>>><<<<>>><<<>>>><<<><<<<>>>><<>>><<<<><>>><<><>>>><<<<><<><<<>><<<<>>>><<>>><<>><<<>><<<>>>><>><>>><<<>><<<<>>>><<<<>>>><>>>><<>><<<<><<>><<>>><<<>><<<<><<<>><<<<>>>><<<<>><<>><<<>>><<>><><>>>><<<>><<<>>><<<<>>><<<<>>><<<<><<<><<<><<<<>>>><<>><<<<>>>><<>>>><<<>>><<><>>><>>>><<<<><<<><<>>>><<<>>>><<<<>><><<<>>><<<<>>><<>><<<>>>><<<>>><<<<><<>>>><<<>>>><<<<><<<<>>>><<<<>><>><<<>>>><>><<>>>><><<<><<<<>><<>><<<<>>>><<>><>>><<>>>><<<>>>><<<<>><<<>><<<<>><>><<>>>><>>><>>><<>>>><<<<>>>><<>>>><<<>><<<<>>>><<<>>><>>>><<<<>>>><<>>>><<<<>><<<><<><<<<>>>><<>>><<><>>>><>><>><>><<<><<<<>><>>>><<<><>>>><<>><<<<><<>>>><<><<<>><<<><<<>>>><<<<><>>>><<<>>>><<<>>><><>><>>><<<>>><<>>><<><<<>>>><>><<<<>>>><>>>><<>>>><<<>>><<<>>>><><><<<<>><<<<>>><><<>><<>>><><<<<><>>><>>>><<<>>><<<<><<<>><<<<>><<<>><<<<><<<><<<<>><<<<>><>>>><<<<>>><>>><>><>>>><<<>><<<>>><<<<>><<<>>>><<<<>><<<>>>><<<>>>><<<>><>><<<>>>><>><<<<>>>><<<<><<>>>><<<><<<>>>><<><<><<>>><<<<><>>>><><<<<>>>><<>>>><<<>>><<><<<<><<>><<>><<<<>>>><<<<>>><>>><<>>><<><<>><<<<><<>>><<<<>><<<>><<<>><><<>>>><<<><<><<<><<<<>>><>>><><<>><<<<>>><>>>><<<<>>><>><<<<>><<<>><<<>>><<<><<>>><<<><<<<>><<<<>>><<<<>>><<<>>><<<><<<<><>>>><<<<>><><<<<>>><<<<>>>><<<><<<<><<><>><<<>><<>>>><><<>>><<<>>>><>>><<<><<<<><<<>><<<<>>><<>><<<>>><<<>>><><<<<><>><<>>>><<>><<<>>><>>>><<<>><<<>>>><<><<<<>><><<<<>>>><<<<>>><<<>><<>><<<>>><<<<>>><<<>>>><>>><<<<><<<>><<><<<>>><<<<>>>><><<>>>><>>>><<<>>>><>>>><<>><<>><>>>><<<>>><<<>>><<<>><>><>>><<<<><>>>><<<><<<>>>><<>>><<<<>>><<<>>><>>>><<<<>>><<>>><<>>>><<<<>>>><>>>><<<>>>><><><<><<>>>><<<>>>><>>>><<<>>><<<<><>>>><>><>><>>><<<<><<><><<<><<>>>><<><<>>><<<<>>>><<<<>>>><<<>><>>>><<<>><<>><<>><>>>><<<>>><<<<><>><<><<<<>>>><<<<>><<<>><><<<<><<<>>><<>>>><<<<>><>>><<<>><<>>><>>><<>>><>>>><<><<<<><>>>><<<>><<<<>>>><<>>><>>>><>>>><<>>><<>><><<>>><<>>><<<>><<<<>><<<>>><>>><<<><>>><<<>>>><<><<<<>><<<<>>>><>>>><<<<>><<>>>><<<>>><<><>><>><<<>>><<<<>><<<<><<>>>><<>><<<>>>><<<<><<<<>>>><<<<>>><<<>>><<>>>><<<<>>><<>><<>><>>>><<>>>><<<><<>>>><<><<>>>><<>>><<>>>><><<<><<<>><<>><<<<>><>>>><<>>><<>><<<<><<><<<><>>>><<<<>>>><<<>>><<<>>>><<<<><<<><<>><<>><<<>>>><>>><<>>><><<>><<<><<<>>><<<><<<>>>><>><<>><<<<>>>><><>>><<<<>>>><>>>><<<>>><>><<<>>><<>>>><<<<>><<<<>>><<<><>>>><>>>><>><<<<>>><><<<<>>><<<<>>>><>><<<>>><<<><>>>><>>><<<>>>><<>><<>><<<>>>><<><><>><<>>><<<><<<><><<<<><<>>>><<<>><<<><<<<>>>><<>><<<<><<<>>>><<<<>>><<<<>>>><<<>><<><>>><<>><<<><<<>><<>>>><<<>>>><>>><<>>><<<>>>><<>>><<<>><<><<>><><<>>><<>>>><<<<>><><<>>>><<>>>><>>>><>><>><<<<>>><>>><<<><>>><<><<><<<><>>><<<><<>>>><<<<>>><<<<>>><<<>><<>>>><<<<>>>><><<<><>>><>>><<>>><<<<>><>><<<>>><<<>><><><<<<>>><>>>><><<>><<<>>>><>>><<<<><<<>><>>>><<><<<<>>><<<<>>>><><<<><<<>>>><><<<>>><<<<>>>><>>>><<<<><><<<<>>>><<>>><>>><><<>>>><<<<>>>><<<<>>>><<<<>><>>>><<<>>><<>>><<<<>><<<><>><<>>><>>><<<>>><<<<>>><<><<<>><<<>><<<<>><<<>><>>><<><<<<>><<>>><<<<><<>>><>>>><>><<<<>>><>>>><><<>>><><>>><<<><>>>><<<>>><<><><<<><<<<>>><<>>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diff --git a/day9/__init__.py b/day9/__init__.py
index e0f1d61..a2d6d82 100644
--- a/day9/__init__.py
+++ b/day9/__init__.py
@@ -1,36 +1,10 @@
 # -*- coding: utf-8 -*-
 from abc import ABC
 from copy import copy
-from dataclasses import dataclass
 from typing import Tuple, Iterator, List, Set
 
 from aoc import BaseAssignment
-
-
-@dataclass
-class Coordinate:
-    x: int
-    y: int
-
-    def __hash__(self):
-        return tuple([self.x, self.y]).__hash__()
-
-    def __sub__(self, other: "Coordinate"):
-        return Coordinate(self.x - other.x, self.y - other.y)
-
-    @property
-    def polarity_x(self):
-        try:
-            return abs(self.x) / self.x
-        except ZeroDivisionError:
-            return 0
-
-    @property
-    def polarity_y(self):
-        try:
-            return abs(self.y) / self.y
-        except ZeroDivisionError:
-            return 0
+from aoc.datastructures import Coordinate
 
 
 class Assignment(BaseAssignment, ABC):
@@ -44,36 +18,44 @@ class Assignment(BaseAssignment, ABC):
         pass
 
     @staticmethod
-    def next_head(head: Coordinate, direction: str):
+    def next_head(head: Coordinate, direction: str) -> Coordinate:
         match direction:
             case "R":
-                head.x += 1
+                return head + Coordinate(1, 0)
             case "L":
-                head.x -= 1
+                return head + Coordinate(-1, 0)
             case "U":
-                head.y += 1
+                return head + Coordinate(0, 1)
             case "D":
-                head.y -= 1
+                return head + Coordinate(0, -1)
 
     @staticmethod
-    def next_knot(head: Coordinate, tail: Coordinate):
+    def next_knot(head: Coordinate, tail: Coordinate) -> Coordinate:
         delta = head - tail
 
         if abs(delta.x) < 2 and abs(delta.y) < 2:
-            pass
+            return tail
         elif abs(delta.x) > 1 and delta.y == 0:
-            tail.x += delta.x - delta.polarity_x
+            return tail + Coordinate(
+                delta.x - delta.polarity_x,
+                0,
+            )
         elif abs(delta.x) > 1 and abs(delta.y) == 1:
-            tail.x += delta.x - delta.polarity_x
-            tail.y += delta.y
+            return tail + Coordinate(delta.x - delta.polarity_x, delta.y)
         elif abs(delta.y) > 1 and delta.x == 0:
-            tail.y += delta.y - delta.polarity_y
+            return tail + Coordinate(
+                0,
+                delta.y - delta.polarity_y,
+            )
         elif abs(delta.y) > 1 and abs(delta.x) == 1:
-            tail.y += delta.y - delta.polarity_y
-            tail.x += delta.x
+            return tail + Coordinate(
+                delta.x,
+                delta.y - delta.polarity_y,
+            )
         elif abs(delta.x) > 1 and abs(delta.y) > 1:
-            tail.x += delta.x - delta.polarity_x
-            tail.y += delta.y - delta.polarity_y
+            return tail + Coordinate(
+                delta.x - delta.polarity_x, delta.y - delta.polarity_y
+            )
 
     def tail_positions(self, input: Iterator[str], length: int) -> Iterator[Coordinate]:
         knots = [Coordinate(0, 0) for _ in range(length)]
@@ -84,10 +66,10 @@ class Assignment(BaseAssignment, ABC):
             for _ in range(amount):
                 for index in range(length):
                     if index == 0:
-                        self.next_head(knots[index], direction)
+                        knots[0] = self.next_head(knots[0], direction)
                         continue
 
-                    self.next_knot(knots[index - 1], knots[index])
+                    knots[index] = self.next_knot(knots[index - 1], knots[index])
 
                 yield knots[length - 1]