Solution: Random Pick with Weight
Explore how to perform weighted random index selection by generating running sums of weights and using a modified binary search. Learn to optimize random picks with respect to weight distribution, achieving better time complexity and practical implementation in Go.
Statement
You’re given an array of positive integers, weights, where weights[i] is the weight of the index.
Write a function, Pick Index(), which performs weighted random selection to return an index from the weights array. The larger the value of weights[i], the heavier the weight is, and the higher the chances of its index being picked.
Suppose that the array consists of the weights . In this case, the probabilities of picking the indexes will be as follows:
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Index 0:
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Index 1:
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Index 2: ...