java实现堆栈、哈希表、链表

//堆栈实现的代码

package traverse;public class Stack {Object[] data;//数据int maxSize;//栈的最大容量int top;//顶点public Stack(int maxSize){this.maxSize=maxSize;data=new Object[maxSize];top=-1;}public int getSize(){return maxSize;}public int getElementCount(){return top;}public boolean isEmpty(){return top==-1;}public boolean isFull(){return top+1==maxSize;}public boolean push(Object data){if(isFull()){System.out.println("栈已满！");return false;}this.data[++top]=data;return true;}public Object pop()throws Exception{if(isEmpty()){throw new Exception("栈已空！");}return this.data[top--];}public Object peek(){return this.data[getElementCount()];}}

二叉树实现代码：

package traverse;public class BinaryTree {private Node root;private static class Node {Node left;Node right;int data;Node(int newData) {left = null;right = null;data = newData;}}/** * 创建一个空的二叉树 */public BinaryTree() {root = null;}/** * 递归的插入数值 * data要插入的数值 */public void insert(int data) {root = insert(root, data);}/** * 将数值插入到二叉树中，比当前结点小或等于当前结点的插在当前结点的左侧，比当前结点大的数插在当前结点的右侧，每次从根结点开始递归比较 * node当前的结点，就是根结点，只是每次根结点的左右子孙更新 * data要插入的数值 * 新排好的二叉树 */private Node insert(Node node, int data) {if (node == null) {node = new Node(data);} else {if (data <= node.data) {node.left = insert(node.left, data);} else {node.right = insert(node.right, data);}}return (node);}/** * 将数值输入构建二叉树 * data要输入的数值 */public void buildTree(int[] data) {for (int i = 0; i < data.length; i++) {insert(data[i]);}}/** * 递归打印出二叉树 */public void printTree() {printTree(root);System.out.println();}/** * 从根结点开始遍历，从树的最高层叶子结点开始输出，从左至右 * node当前的结点 */private void printTree(Node node) {if (node == null)return;// left, node itself, rightprintTree(node.left);System.out.print(node.data + "  ");printTree(node.right);}}

哈希表代码：

package traverse;public class HashTable{   private String[] name;    //关键字   private int sum;    //容量     public HashTable(){             //初始化，初始容量是10个      name = new String[10];      sum = 0;  }  public int hash1(String s){                                       //哈希函数        return Math.abs(s.hashCode())%name.length;  }  public int hash2(String s){                                     //处理冲突的哈希函数      int result = Math.abs(s.hashCode())%(name.length-1);      System.out.println(s+"--"+result);      if(result%2==0){          return result + 1;      }   return result;  }   public boolean contains(String s){                  //哈希表里面是否包含字符串s      int start = hash1(s);      int i = start;      while (name[i] != null){           if(name[i].equals(s)){               return true;           }        i = (i + hash2(s))%name.length;        if(i == start){             return false;        }      }   return false;  }  public void add(String s){       if(sum>=name.length/2){            this.rehash();       }      int start = hash1(s);      int i = start;     while(name[i] != null){         if(s.equals(name[i])){              return;         }       i = (i + hash2(s))%name.length;      if(i == start){          return;       }     }    name[i] = s;    sum ++;  }   public void rehash(){                              //扩建一个哈希表为原表的两倍，把原来的哈希表添加到新表中       HashTable ht = new HashTable();       ht.name = new String[this.name.length * 2];       for(int i = 0; i < this.name.length; i ++){               if((this.name[i] != null)){                   ht.add(this.name[i]);              }       }     this.name = ht.name;     this.sum = ht.sum;   }      public void remove(String s){                     //删除某个元素         if(this.contains(s)){              int i = this.getValue(s);              this.name[i] = null;         }  }   public int getValue(String s){                //得到s在哈希表中的位置    int start = this.hash1(s);    int i = start;    while(this.name[i] != null){       if(this.name[i].equals(s)){           return i;       }     i = (i + this.hash2(s))%this.name.length;    if(i == start){      return -1;     }   }  return -1;  }  public void print(){                       //输出哈希表中所有元素     for(int i = 0; i < name.length; i ++){        System.out.println(i+":"+name[i]);    }  }public int size(){          //哈希表存储元素的个数   return this.sum; }public int length(){            //哈希表的长度    return this.name.length; }}

主函数遍历：

package traverse;import traverse.BinaryTree;import traverse.Stack;import traverse.HashTable;public class traverse {public static void main(String[] args) throws Exception {  BinaryTree tree=new BinaryTree(); int[] data = { 2, 8, 7, 4 ,9,3,1,6,7,5};        tree.buildTree(data);       tree.printTree();           HashTable table = new HashTable();     table.add("one");     table.add("two");     table.add("three");     table.add("four");     table.add("fve");     table.add("six");     System.out.println(table.contains("two"));     table.remove("six");     System.out.println(table.contains("six"));     table.print();          Stack stack=new Stack(100);     stack.push(new String("1"));     stack.push(new String("2"));     stack.push(new String("3"));     stack.push(new String("4"));     stack.push(new String("5"));     while(!stack.isEmpty())     {     System.out.print(stack.peek());     stack.pop();     }}}