59 lines
1.4 KiB
Python
59 lines
1.4 KiB
Python
#!/usr/bin/env python3
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from collections import defaultdict
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from array import array
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def main(initial_suite, max_iteration):
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iteration = 1
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seen = defaultdict(int)
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# init
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for number in initial_suite:
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seen[number] = iteration
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iteration += 1
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current = 0
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while iteration < max_iteration:
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last_seen = seen[current]
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if last_seen == 0:
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seen[current] = iteration
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current = 0 # next
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else:
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seen[current] = iteration
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current = iteration - last_seen # next
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iteration += 1
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return current
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def main_array(initial_suite, max_iteration):
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iteration = 1
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seen = array('I', [0] * max_iteration)
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# init
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for number in initial_suite:
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seen[number] = iteration
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iteration += 1
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current = 0
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while iteration < max_iteration:
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last_seen = seen[current]
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if last_seen == 0:
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seen[current] = iteration
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current = 0 # next
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else:
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seen[current] = iteration
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current = iteration - last_seen # next
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iteration += 1
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return current
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if __name__ == "__main__":
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inp = [6, 3, 15, 13, 1, 0]
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# 423 µs ± 53.9 µs per loop (mean ± std. dev. of 7 runs, 1000 loops each)
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print(main(inp, 2020))
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# 13.6 s ± 2.89 s per loop (mean ± std. dev. of 7 runs, 1 loop each)
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#print(main(inp, 30000000))
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print(main_array(inp, 30000000))
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