16 lines
246 B
Python
16 lines
246 B
Python
def helper(n: u64, a: u64, b: u64) -> u64:
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if n < 1:
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return a + b
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return helper(n - 1, a + b, a)
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@exported
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def fib(n: u64) -> u64:
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if n == 0:
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return 0
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if n == 1:
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return 1
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return helper(n - 1, 0, 1)
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