melotang

摘要： 终于把《数据库系统基础教程》给大概翻完了，江苏的真题也做了一套，还有最后10题，后天晚上搞定吧。现在的目标1.马士兵的面试题2.mysql必知必会3.复习其他基础 阅读全文

摘要： 最近意识到自己很懒，什么都不想动，天天就看看NBA，唉。。。。。。还是定个学习计划吧，也不知道未来会怎么样，一年后的自己到底会变成啥样。这两天希望做到如下：你可以安装MSSQLServer或MySQL来学习数据库。学习教科书里数据库设计的那几个范式，1NF，2NF，3NF，……学习数据库的存取，触发器，视图，建索引，游标等。学习SQL语句，明白表连接的各种概念（参看《SQL Join的图示》）学习如何优化数据库查询（参看《MySQL的优化》）实践任务：设计一个论坛的数据库，至少满足3NF，使用SQL语句查询本周，本月的最新文章，评论最多的文章，最活跃用户。 阅读全文

摘要： 1 public class LinkedList { 2 3 private Node header=null; 4 private Node tail=null; 5 6 /** 7 * @param data 8 */ 9 public void add(int data){10 if(header==null){11 Node newnode=new Node();12 newnode.setData(data);13 new... 阅读全文

摘要： 1 public class OpenaddressHashtable { 2 3 private int[] hashtable; 4 private int hashsize; 5 6 public OpenaddressHashtable(int size){ 7 hashsize=size; 8 hashtable=new int[hashsize]; 9 }10 11 public int hashFunc(int key){12 return key%hashsiz... 阅读全文

摘要： 1 public class ChainingHashtable { 2 3 private static class Node{ 4 private int key; 5 private String value; 6 private Node next; 7 8 public Node(int key,String value){ 9 this.key=key; 10 this.value=value; 11 ... 阅读全文

摘要： 这篇博客主要探讨Hash表中的一些原理/概念，及根据这些原理/概念，自己设计一个用来存放/查找数据的Hash表，并且与JDK中的HashMap类进行比较。我们分一下七个步骤来进行。一。 Hash表概念二 . Hash构造函数的方法，及适用范围三.Hash处理冲突方法，各自特征四.Hash查找过程五.实现一个使用Hash存数据的场景-------Hash查找算法，插入算法六.JDK中HashMap的实现七.Hash表与HashMap的对比，性能分析一。 Hash表概念 在查找表中我们已经说过，在Hash表中，记录在表中的位置和其关键字之间存在着一种确定的关系。这样 我们... 阅读全文

摘要： Abinary treeis atree data structurein which each node has at most twochild nodes, usually distinguished as "left" and "right". Nodes with children areparent nodes, and child nodes may contain references to their parents. Outside the tree, there is often a reference to the "r 阅读全文

摘要： Queueis a particular kind ofabstract data typeorcollectionin which the entities in the collection are kept in order and the principal (or only) operations on the collection are the addition of entities to the rear terminal position, known asenqueue,and removal of entities from the front terminal pos 阅读全文

摘要： Stackis a particular kind ofabstract data typeorcollectionin which the principal (or only) operations on the collection are the addition of an entity to the collection, known aspushand removal of an entity, known aspop.The relation between the push and pop operations is such that the stack is aLast- 阅读全文

摘要： Bucket sort, orbin sort, is asorting algorithmthat works by partitioning anarrayinto a number ofbuckets. Each bucket is then sorted individually, either using a different sorting algorithm, or by recursively applying the bucket sorting algorithm. It is adistribution sort, and is a cousin ofradix sor 阅读全文