“…The inner product search (IPS) problem is important in many fields, e.g., information retrieval [18,32,35], recommender systems [6,7,30], data mining [19,27], databases [22,24,29], artificial intelligence [13,36], and machine learning [14,23,34]. These fields usually consider the 𝑘 maximum inner product search (𝑘-MIPS) problem, which, given a query vector and an output size 𝑘, returns the 𝑘 vectors having the maximum inner product with the query.…”