a weakness of hashing Problem: For any hash function h, a set of keys exists that can cause the average access time of a hash table to skyrocket An adversary can pick all keys from tkeU: h(k)=i for some slot i IDEA Choose the hash function at random independently of the keys

Balanced search trees Balanced search tree a search-tree data structure for which a height of o(g n)is guaranteed when implementing a dynamic set of n items

Computational geometry Algorithms for solving geometric problems in 2D and higher Fundamental objects: o point line segment

How large should a hash table be? Goal: Make the table as small as possible but large enough so that it wont overflow(or otherwise become inefficient Problem: what if we don 't know the proper size

Graphs(review) Definition. a directed graph(digraph G=(, E)is an ordered pair consisting of a set y of vertices(singular: vertex) a sete c× of edges. In an undirected graphG=(V, E), the edge set e consists of unordered pairs of vertices In either case, we have El=O(v2).Moreover if G is connected, then E2v-l, which

Negative-weight cycles Recall: If a graph G=(V, E) contains a negative weight cycle then some shortest paths may not exist

由6.1知定积分是一个复杂和式的极限,但要想通过 求积分和的极限来得到定积分的值,却非常困难;下面 寻求一种计算定积分的非常简便的新方法——牛顿莱布 尼兹(Netwon-Laibniz-)公式计算法. 一.积分上限函数

4.1 程序的装入和链接 4.2 连续分配方式 4.3 基本分页存储管理方式 4.4 基本分段存储管理方式 4.5 虚拟存储器的基本概念 4.6 请求分页存储管理方式 4.7 页面置换算法 4.8 请求分段存储管理方式

第五章多目标规划 1.问题的提出与目标规划的数学模型 2.目标规划的图解分析法 3.用单纯形法求解目标规划 4.求解目标规划的层次算法 5.应用举例

西安电子科技大学：《现代密码学》课程教学资源（PPT课件讲稿）第三章 流密码（线性反馈移位寄存器序列、B-M综合算法、非线性序列）