[2022][day 9] adding solution

2022/AOC09.py

@@ -0,0 +1,88 @@
+from typing import List, Tuple, Set
+
+from _utils import read_input, timer, Solution, Point
+
+
+def process_input(filename: str):
+ _input = read_input(filename)
+ return _input
+
+
+def get_neighbors(head: Point, tail: Point) -> bool:
+ x, y = head
+ neighbors = [(x + dx, y + dy) for dx in range(-1, 2) for dy in range(-1, 2)]
+ return tail in neighbors
+
+
+def move_head(direction: str, x: int, y: int) -> Point:
+ if direction == "R":
+ x += 1
+ elif direction == "L":
+ x -= 1
+ elif direction == "U":
+ y -= 1
+ elif direction == "D":
+ y += 1
+ return x, y
+
+
+def adjust_tail(head: Point, tail: Point) -> Point:
+ x, y = head
+ x2, y2 = tail
+
+ if get_neighbors(head, tail):
+ return tail
+ elif (y == y2) and x2 - x == 2:
+ x2 -= 1 # right
+ elif (y == y2) and x - x2 == 2:
+ x2 += 1 # left
+ elif (x == x2) and y - y2 == 2:
+ y2 += 1 # down
+ elif (x == x2) and y2 - y == 2:
+ y2 -= 1 # up
+ elif x > x2 and y < y2: # top right
+ x2 += 1 # right
+ y2 -= 1 # up
+ elif x > x2 and y > y2: # bottom right
+ x2 += 1 # right
+ y2 += 1 # down
+ elif x < x2 and y > y2: # bottom left
+ x2 -= 1 # left
+ y2 += 1 # down
+ elif x < x2 and y < y2: # top left
+ x2 -= 1 # left
+ y2 -= 1 # up
+ else:
+ raise Exception
+
+ return (x2, y2)
+
+
+def simulate(_input: List[str], len_rope: int = 2) -> int:
+ knots = [(0, 0) for i in range(len_rope)]
+ visited = set()
+
+ for line in _input:
+ direction, step = line.split(" ")
+ for r in range(int(step)):
+ new_knots = [k for k in knots]
+ new_knots[0] = move_head(direction, *new_knots[0])
+ for i in range(1, len_rope):
+ new_knots[i] = adjust_tail(new_knots[i - 1], new_knots[i])
+ visited.add(new_knots[-1])
+ knots = new_knots
+ return len(visited)
+
+
+@timer
+def main(filename: str) -> Solution:
+ _input = process_input(filename)
+ part_1_solution = simulate(_input, len_rope=2)
+ part_2_solution = simulate(_input, len_rope=10)
+ return part_1_solution, part_2_solution
+
+
+if __name__ == "__main__":
+ part_1_solution, part_2_solution = main("aoc9.txt")
+ print(f"PART 1: {part_1_solution}") # 6470
+ print(f"PART 2: {part_2_solution}") # 2658