54 lines
976 B
Python
54 lines
976 B
Python
#!/usr/bin/env python
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"""
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Created on 11 Sep 2019
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@author: David Doblas Jiménez
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@email: daviddoji@pm.me
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Solution for problem 025 of Project Euler
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https://projecteuler.net/problem=25
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"""
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from utils import timeit
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@timeit("Problem 025")
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def compute():
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"""
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The Fibonacci sequence is defined by the recurrence relation:
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Fn = Fn-1 + Fn-2, where F1 = 1 and F2 = 1.
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Hence the first 12 terms will be:
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F1 = 1
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F2 = 1
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F3 = 2
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F4 = 3
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F5 = 5
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F6 = 8
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F7 = 13
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F8 = 21
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F9 = 34
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F10 = 55
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F11 = 89
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F12 = 144
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The 12th term, F12, is the first term to contain three digits.
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What is the index of the first term in the Fibonacci sequence to
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contain 1000 digits?
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"""
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a, b = 1, 1
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ans = 2
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while len(str(b)) < 1000:
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a, b = b, b + a
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ans += 1
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return ans
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if __name__ == "__main__":
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print(f"Result for Problem 025: {compute()}")
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