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7f6e0b656f
* Moved fractional knapsack from 'dynamic_programming' to 'greedy_methods' * Updated DIRECTORY.md
28 lines
578 B
Python
28 lines
578 B
Python
from bisect import bisect
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from itertools import accumulate
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def frac_knapsack(vl, wt, w, n):
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"""
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>>> frac_knapsack([60, 100, 120], [10, 20, 30], 50, 3)
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240.0
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"""
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r = sorted(zip(vl, wt), key=lambda x: x[0] / x[1], reverse=True)
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vl, wt = [i[0] for i in r], [i[1] for i in r]
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acc = list(accumulate(wt))
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k = bisect(acc, w)
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return (
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0
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if k == 0
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else sum(vl[:k]) + (w - acc[k - 1]) * (vl[k]) / (wt[k])
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if k != n
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else sum(vl[:k])
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)
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if __name__ == "__main__":
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import doctest
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doctest.testmod()
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