forked from YovM/Algorithms
49 lines
960 B
Python
49 lines
960 B
Python
"""
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Project Euler Problem 2: https://projecteuler.net/problem=2
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Even Fibonacci Numbers
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Each new term in the Fibonacci sequence is generated by adding the previous
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two terms. By starting with 1 and 2, the first 10 terms will be:
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1, 2, 3, 5, 8, 13, 21, 34, 55, 89, ...
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By considering the terms in the Fibonacci sequence whose values do not exceed
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four million, find the sum of the even-valued terms.
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References:
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- https://en.wikipedia.org/wiki/Fibonacci_number
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"""
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def solution(n: int = 4000000) -> int:
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"""
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Returns the sum of all even fibonacci sequence elements that are lower
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or equal to n.
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>>> solution(10)
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10
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>>> solution(15)
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10
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>>> solution(2)
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2
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>>> solution(1)
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0
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>>> solution(34)
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44
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"""
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i = 1
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j = 2
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total = 0
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while j <= n:
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if j % 2 == 0:
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total += j
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i, j = j, i + j
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return total
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if __name__ == "__main__":
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print(f"{solution() = }")
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