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arXiv · 2311.01213

Hybrid classical-quantum text search based on hashing

Farid Ablayev·Marat Ablayev·Nailya Salikhova
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Abstract

The paper considers the problem of finding a given substring in a text. It is known that the complexity of a classical search query in an unordered database is linear in the length of the text and a given substring. At the same time, Grover's quantum search provides a quadratic speedup in the complexity of the query and gives the correct result with a high probability. We propose a hybrid classical-quantum algorithm (hybrid random-quantum algorithm to be more precise), that implements Grover's search to find a given substring in a text. As expected, the algorithm works a) with a high probability of obtaining the correct result and b) with a quadratic query acceleration compared to the classical one. What's new is that our algorithm uses the uniform hash family functions technique. As a result, our algorithm is much more memory efficient (in terms of the number of qubits used) compared to previously known quantum algorithms.

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Farid Ablayev, Marat Ablayev, Nailya Salikhova. 2023-11-02. Hybrid classical-quantum text search based on hashing. https://arxiv.org/abs/2311.01213

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