Streaming algorithms for monotone non-submodular function maximization under a knapsack constraint on the integer lattice

The study of non-submodular maximization on the integer lattice is an important extension of submodular optimization. In this paper, streaming algorithms for maximizing non -negative monotone non-submodular functions with knapsack constraint on integer lattice are considered. We first design a two-pass StreamingKnapsack algorithm combining with BinarySearch as a subroutine for this problem. By introducing the DR ratio gamma and the weak DR ratio gamma w of the non-submodular objective function, we obtain that the approximation ratio is min{gamma 2(1 - epsilon)/2 gamma +1, 1 - 1/gamma w2 gamma - epsilon}, the total memory complexity is O (K log K /epsilon), and the total query complexity for each element is O (log K log(K/epsilon 2)/epsilon). Then, we design a one-pass streaming algorithm by dynamically updating the maximal function value among unit vectors along with the currently arriving element. Finally, in order to decrease the memory complexity, we design an improved StreamingKnapsack algorithm and reduce the memory complexity to O (K /epsilon 2).(c) 2022 Elsevier B.V. All rights reserved.