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59 lines
1.6 KiB
Python
59 lines
1.6 KiB
Python
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from collections import Counter
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import itertools
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import math
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lines = { int(x) for x in open('input').read().splitlines() }
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lines.add(0)
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def a(transformers):
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v = 0
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dv = [3] #Always a 3 v transform at the end
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while v < max(transformers):
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v_ = min(set(range(v+1,v+4)).intersection(transformers))
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dv.append(v_ - v)
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v = v_
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# print(dv)
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count = dict(Counter(dv))
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return count[3]*count[1]
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# print(lines)
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# This is a recursive solution. IT works but it'll take an eternity to go through the whole list of transformers.
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# Instead, we split
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def b(c, v, transformers):
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for v_ in set(range(v+1,v+4)).intersection(lines):
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# print(v_)
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if v_ == max(transformers):
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c += 1
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else:
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c = b(c, v_, transformers)
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return c
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# print(b(0, 0, lines)) #Does not work for big sets!
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# print(b(0, 1, {1, 2, 3, 4}))
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# print(b(0, 7, {7, 8, 9, 10, 11}))
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def b_optimized(transformers):
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rel = { v: set(range(v+1,v+4)).intersection(transformers) for v in transformers }
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rel.pop(max(transformers))
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# print(rel)
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# print({ x if (vf in rel[x]) else None for x in rel }.intersection(transformers))
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gaps = { list(rel[x])[0] if (len(rel[x]) == 1) else None for x in rel }.intersection(transformers)
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gaps.add(list(rel)[0])
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gaps = sorted(gaps)
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# print(gaps)
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idx = 0
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C = 1
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while idx+1 < len(gaps):
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s = sorted(set(range(gaps[idx],gaps[idx+1]+1)).intersection(transformers))
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# print(s)
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if len(s) > 2:
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C *= b(0, list(s)[0], s)
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# print(C, b(0, list(s)[0], s))
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idx += 1
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return C
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print(a(lines))
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print(b_optimized(lines))
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