Priority Queues with Multiple Time Fingers

A priority queue is presented that supports the operations insert and find-min in worst-case constant time, and delete and delete-min on element x in worst-case O(lg(min{w_x, q_x}+2)) time, where w_x (respectively q_x) is the number of elements inserted after x (respectively before x) and are still present at the time of the deletion of x. Our priority queue then has both the working-set and the queueish properties, and more strongly it satisfies these properties in the worst-case sense. We also define a new distribution-sensitive property---the time-finger property, which encapsulates and generalizes both the working-set and queueish properties, and present a priority queue that satisfies this property. In addition, we prove a strong implication that the working-set property is equivalent to the unified bound (which is the minimum per operation among the static finger, static optimality, and the working-set bounds). This latter result is of tremendous interest by itself as it had gone unnoticed since the introduction of such bounds by Sleater and Tarjan [JACM 1985]. Accordingly, our priority queue satisfies other distribution-sensitive properties as the static finger, static optimality, and the unified bound.Comment: 14 pages, 4 figure

The Fresh-Finger Property

The unified property roughly states that searching for an element is fast when the current access is close to a recent access. Here, "close" refers to rank distance measured among all elements stored by the dictionary. We show that distance need not be measured this way: in fact, it is only necessary to consider a small working-set of elements to measure this rank distance. This results in a data structure with access time that is an improvement upon those offered by the unified property for many query sequences

Smooth heaps and a dual view of self-adjusting data structures

We present a new connection between self-adjusting binary search trees (BSTs) and heaps, two fundamental, extensively studied, and practically relevant families of data structures. Roughly speaking, we map an arbitrary heap algorithm within a natural model, to a corresponding BST algorithm with the same cost on a dual sequence of operations (i.e. the same sequence with the roles of time and key-space switched). This is the first general transformation between the two families of data structures. There is a rich theory of dynamic optimality for BSTs (i.e. the theory of competitiveness between BST algorithms). The lack of an analogous theory for heaps has been noted in the literature. Through our connection, we transfer all instance-specific lower bounds known for BSTs to a general model of heaps, initiating a theory of dynamic optimality for heaps. On the algorithmic side, we obtain a new, simple and efficient heap algorithm, which we call the smooth heap. We show the smooth heap to be the heap-counterpart of Greedy, the BST algorithm with the strongest proven and conjectured properties from the literature, widely believed to be instance-optimal. Assuming the optimality of Greedy, the smooth heap is also optimal within our model of heap algorithms. As corollaries of results known for Greedy, we obtain instance-specific upper bounds for the smooth heap, with applications in adaptive sorting. Intriguingly, the smooth heap, although derived from a non-practical BST algorithm, is simple and easy to implement (e.g. it stores no auxiliary data besides the keys and tree pointers). It can be seen as a variation on the popular pairing heap data structure, extending it with a "power-of-two-choices" type of heuristic.Comment: Presented at STOC 2018, light revision, additional figure

Resumos...

Plant perception of insect herbivores; Voláteis de plantas induzidos por insetos e sua interação com inimigos naturais: relato de pesquisas no Brasil; Semioquimicos envolvidos na atração do principal vetor da leishmaniose viceral nas Américas; Ecologia química da broca da erva mate, Hedypathes betulinus (Coleoptera: Cerambycidae; Changing publishing dynamics in chemical ecology; J. Braz. Chem. Soe., o Periódico Internacional da Sociedade Brasileira de Química; Publicação de resultados em ecologia química nos periódicos da Sociedade Entomológica do Brasil: Neotropical Entomology e Bioassay; Seleção da planta hospedeira for fêmeas de Tuta absoluta (Lepidoptera: Gelechiidae; Semioquímicos de sistemas tritróficos: planta-inseto herbívoro- parasitóide de ovos; Alelopatia em sistemas de produção agrícola: avanços e aplicações; Economical chemical ecology: discovering semiochemicals for agriculture and medical entomology; Avanços científicos na ecologia química marinha atual (=ecológica) e histórica (=evolutiva); Fluxos de nutrientes de animais para plantas: testes com isótopos estáveis; Respostas da soja a estresses bióticos e abióticos; Produtos naturais no controle de insetos pragas; Stress signalling in plants and animals: novel sustainable approaches to insect pest control in the 21st. century; Identification and synthesis of biologically active compounds from Caddisflies (Trichoptera); Defesa química em anfíbios; Proteomic analysis to understand pathways of resistance to Aspergíllus flavus infection and aflatoxin accumulation in maize; Semioquímicos: da bancada de laboratório a sua aplicação em programas de controle do mosquito Aedes aegypti, vetor da dengue; Influência de extratos do fruto do tomate na oviposição de Neoleucinodes elegantalis (Lepidoptera: Crambidae); Monitoramento e controle de mosca-das-frutas Anastrepha fraterculus (Wiedemann) com atrativo alimentar bio anastrepha, bio fruit e fenthion, em videira; Resposta olfativa do parasitóide de ovos Telenomus remus nixon (Hymenoptera: Scelionidae) a voláteis da planta de milho induzidos pela alimentação de Spodoptera frugiperda (JE Smith) (Lepidoptera: Noctuidae); Atividade de repelência de óleos essênciais de duas espécies de eucalipto frente ao pulgão do algodoefro, Aphis gossypii Glover (Hemiptera: Aphididae); Atividade de deterrente de oviposição de alguns óleos essenciais da flora brasileira frente à fêmea de Aedes aegypti; Glucosinolatos em brássicas e efeito de cultivares sobre a traça-dascrucíferas, discriminado por meio de análise multivariada; Efeito de extrato aquoso de Melia azedarach no desenvolvimento de Spodoptera frugiperda (J. E Smith, 1797) (Lepidoptera: Noctuidae); Differential attack of Cryptoblabes gnidiella (Lepidoptera: Pyralidae) to comercial grapevine varieties, in search of volatile-mediated oviposition preferences; Influência da herbivoria em soja na seleção de plantas hospedeiras pelo percevejo marram Euschistus heras (Hemiptera: Pentatomidae); Resposta olfativa do parasitóide larval Campoletis flavicincta (Ashmead) (Hymenoptera: Ichneumonidae) a voláteis de planta de milho induzidos pela herbivoria de Spodoptera frugiperda (JE Smith) (Lepidoptera: Noctuidae); Avaliação da atividade inseticida de óleos vegetais em Nezara viridula var. smaragdula (Hemiptera, Pentatomidae);Organizado por Clara Beatriz Hoffmann-Campo, Odilon Ferreira Saraiva, Lenita Jacob Oliveira, Odilon Ferreira Saraiva, Simone Ery Grosskopf

Queaps

SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Queaps

Proceedings of the 13th Annual International Symposium on Algorithms and Computation (ISAAC 2002)info:eu-repo/semantics/publishe