33 lines
763 B
Python
33 lines
763 B
Python
with open("input.txt","r") as f:
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lines = f.read().split('\n')
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orbits = {}
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for line in lines:
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parent, child = line.split(')')
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orbits[child] = parent
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def depth(node, graph):
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depth = 1
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parent = graph[node]
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while parent != "COM":
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depth += 1
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parent = graph[parent]
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return depth
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def parents(node, graph):
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path = []
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parent = graph[node]
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while parent != "COM":
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path.append(parent)
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parent = graph[parent]
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return path
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def orbital_transfers(start, end, graph):
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path1 = parents(start, graph)
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path2 = parents(end, graph)
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set1 = set(path1)
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set2 = set(path2)
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return len((set1 - set2) | (set2 - set1)) # union of differences
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part1 = sum([depth(x, orbits) for x in orbits.keys()])
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part2 = orbital_transfers("YOU", "SAN", orbits)
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print(part1, part2) |