109 lines
2.6 KiB
Python
109 lines
2.6 KiB
Python
import time
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from os import system
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moves = []
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input_file = open("input.txt", "r")
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lines = input_file.readlines()
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for line in lines:
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line = line.strip()
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moves.append((line[0], int(line.split(" ")[-1])))
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# Part 1
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head = (0, 0)
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tail = (0, 0)
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visited_positions = {tail}
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def get_knot_new_pos(front_knot, knot):
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x_diff = front_knot[0] - knot[0]
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y_diff = front_knot[1] - knot[1]
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if abs(x_diff) <= 1 and abs(y_diff) <= 1:
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return knot
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new_x = knot[0]
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new_y = knot[1]
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if abs(x_diff) > 1 and abs(y_diff) > 1:
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new_x = knot[0] + x_diff // 2
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new_y = knot[1] + y_diff // 2
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elif abs(x_diff) > 1 and abs(y_diff) >= 1:
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new_x = knot[0] + x_diff // 2
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new_y = knot[1] + y_diff
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elif abs(y_diff) > 1 and abs(x_diff) >= 1:
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new_y = knot[1] + y_diff // 2
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new_x = knot[0] + x_diff
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elif abs(x_diff) > 1:
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new_x = knot[0] + x_diff // 2
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elif abs(y_diff) > 1:
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new_y = knot[1] + y_diff // 2
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return (new_x, new_y)
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for move in moves:
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for _ in range(move[1]):
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if move[0] == "U":
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head = (head[0] + 1, head[1])
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elif move[0] == "D":
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head = (head[0] - 1, head[1])
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elif move[0] == "R":
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head = (head[0], head[1] + 1)
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elif move[0] == "L":
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head = (head[0], head[1] - 1)
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tail = get_knot_new_pos(head, tail)
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visited_positions.add(tail)
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print("Part 1: " + str(len(visited_positions)))
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# Part 2
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head = (0, 0)
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knots = [(0, 0) for _ in range(1, 10)]
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def print_grid():
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system('clear')
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for x in range(-10, 10):
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for y in range(-10, 10):
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to_print = "."
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if (-x, y) == (0, 0):
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to_print = "s"
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if (-x, y) in knots:
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to_print = str(knots.index((-x, y)) + 1)
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if (-x, y) == head:
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to_print = "H"
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print(to_print, end="")
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print()
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visited_positions = {knots[-1]}
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for move in moves:
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for _ in range(move[1]):
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if move[0] == "U":
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head = (head[0] + 1, head[1])
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elif move[0] == "D":
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head = (head[0] - 1, head[1])
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elif move[0] == "R":
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head = (head[0], head[1] + 1)
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elif move[0] == "L":
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head = (head[0], head[1] - 1)
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for i in range(len(knots)):
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# for debugging purposes
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# print_grid()
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# input("_")
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if i == 0:
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knots[i] = get_knot_new_pos(head, knots[i])
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else:
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knots[i] = get_knot_new_pos(knots[i - 1], knots[i])
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visited_positions.add(knots[-1])
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print("Part 2: " + str(len(visited_positions)))
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