Имеем некоторую константу A, $0 < A < 1$.

1. key * A
2. Взять дробную часть от результата

$h(key) = \lfloor ((key*A)\space mod \space 1) * m \rfloor$

<aside> ℹ️ In practice, the multiplication method is best in the special case where the number m of hash-table slots is an exact power of 2, so that $m = 2^l$ for some $l <= w$. Introduction to Algorithms (Fourth Edition) - Thomas H. Cormen, Charles E. Leiserson, Ronald L. Rivest, Clifford Stein (2022)

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