22 lines
448 B
Python
22 lines
448 B
Python
import random
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def find_duplicate(xs):
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print(xs)
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# entry point in our cycle is the duplicate
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i = xs[0]
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j = xs[xs[0]]
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while i != j:
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print(i, xs[i], j, xs[j])
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i = xs[i]
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j = xs[xs[j]]
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# detect cycle
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j = 0
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while i != j:
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i = xs[i]
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j = xs[j]
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return xs[i]
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n = random.randint(5, 10)
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xs = [random.randint(0, n - 1) for _ in range(n)]
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result = find_duplicate(xs)
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print(xs, result)
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