Rick van Hattem
30 lines
663 B
Python
30 lines
663 B
Python
# Implement the quicksort algorithm.
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import random
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# one-liner approach
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qs = lambda xs: xs if len(xs) <= 1 else qs(
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[x for x in xs[1:] if x < xs[0]]) + [xs[0]] + qs(
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[x for x in xs[1:] if x >= xs[0]])
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# more verbose approach
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def quicksort(xs):
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if len(xs) <= 1:
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return xs
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else:
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left = quicksort([x for x in xs[1:] if x < xs[0]])
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right = quicksort([x for x in xs[1:] if x >= xs[0]])
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middle = [xs[0]]
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return left + middle + right
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def main():
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# test
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xs = random.sample(range(1000), 100)
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assert quicksort(xs) == sorted(xs)
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assert qs(xs) == sorted(xs)
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if __name__ == '__main__':
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main()
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