76 lines
2 KiB
Python
76 lines
2 KiB
Python
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import re
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EX0 = ["R8,U5,L5,D3", "U7,R6,D4,L4"]
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EX1 = ["R75,D30,R83,U83,L12,D49,R71,U7,L72", "U62,R66,U55,R34,D71,R55,D58,R83"]
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EX2 = ["R98,U47,R26,D63,R33,U87,L62,D20,R33,U53,R51", "U98,R91,D20,R16,D67,R40,U7,R15,U6,R7"]
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def main():
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with open("day3.txt", "rt") as input_file:
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lines = list(input_file.readlines())
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solve(lines)
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def solve(input_lines):
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wires = [(wire_id, line.strip().split(",")) for wire_id, line in enumerate(input_lines)]
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grid = compute_grid(wires)
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intersections = get_intersections(grid)
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# print("Intersections:", intersections)
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distances = get_manhattan_distances(intersections)
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# print("Distances:", distances)
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print("Min:", min(distances))
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def compute_grid(wires):
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grid = {}
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for wire_id, codes in wires:
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fill_grid(wire_id, codes, grid)
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return grid
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CODE_RE = re.compile(r"(\w)(\d+)")
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def fill_grid(wire_id, codes, grid):
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x = 0
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y = 0
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for code in codes:
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match = CODE_RE.match(code)
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op, arg = match.groups()
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for _ in range(int(arg)):
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if op == "R":
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y += 1
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elif op == "L":
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y -= 1
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elif op == "U":
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x += 1
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elif op == "D":
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x -= 1
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inc_point((x, y), grid, wire_id)
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def inc_point(point, grid, wire_id):
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x, y = point
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if x not in grid:
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grid[x] = {}
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if y not in grid[x]:
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grid[x][y] = [wire_id]
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elif wire_id not in grid[x][y]:
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grid[x][y].append(wire_id)
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def get_intersections(grid):
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intersections = []
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for x, line in grid.items():
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for y, wire_ids in line.items():
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if len(wire_ids) > 1:
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intersections.append((x, y))
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return intersections
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def get_manhattan_distances(points):
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distances = []
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for point in points:
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distances.append(manhattan_dist((0, 0), point))
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return distances
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def manhattan_dist(p1, p2):
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p1x, p1y = p1
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p2x, p2y = p2
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return abs(p1x - p2x) + abs(p1y - p2y)
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if __name__ == "__main__":
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main()
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