20 lines
472 B
Python
20 lines
472 B
Python
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import random
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def find_pairs(xs, n):
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"""
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Return all pairs of integers in `xs` that sum to `n`.
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"""
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seeking = set()
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result = set()
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for x in xs:
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if x in seeking:
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result.add((n - x, x))
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else:
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seeking.add(n - x)
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return result
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xs = [random.randint(1, 10) for _ in range(10)]
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n = random.randint(1, 10) + random.randint(1, 10)
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print("Seeking all pairs in {} for {}...".format(xs, n))
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print(find_pairs(xs, n))
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