2021-01-28 13:43:59 +01:00
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def pgcd(a, b):
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#@ requires a > 0 and b > 0
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while a != b:
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#@ invariant a > 0 and b > 0
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#@ variant a + b
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if a < b:
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2021-06-23 17:45:21 +02:00
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b -= a
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2021-01-28 13:43:59 +01:00
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else:
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2021-06-23 17:45:21 +02:00
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a -= b
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2021-01-28 13:43:59 +01:00
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return a
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