18 lines
302 B
Python
18 lines
302 B
Python
def fib(n: int):
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"""Return n-th Fibonacci number.
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>>> fib(10)
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55
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>>> fib(1)
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1
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>>> fib(8)
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21
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"""
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if n <= 0:
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return 0
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elif n == 1:
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return 1
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else:
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a, b = 0, 1
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for _ in range(2, n + 1):
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a, b = b, a + b
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return b |