Java数据结构的一些基础（更新完成）

1，输入方法

java.util.Scanner类

<pre name="code" class="java">Scanner scan=new Scanner(System.in);

通过scan调用下列方法：

next()：读写字符串

nextInt() ：读写整形数据

nextFloat() ：读写浮点

nextDouble() ：

nextLine() ：读取一行数据

nextByte() ：读取字节数据

2，随机数

Math.random()表示从0到1内的随机数。

(int)限定为整型，*2即0->2之间的数，不包括2。

class createRandom{
 private int random;
 
 public int getRandom(){
  random=(int)(Math.random()*2);
  return random;
  }
 }
 
public class RandomNumber{
 public static void main(String[] args){
  createRandom cr=new createRandom();
  System.out.println(cr.getRandom());
  }
 }

3.线性表的基础练习，基本操作详细设计

T1：基本操作结构

package ch2;
import java.util.PrimitiveIterator.OfDouble;
import java.util.Scanner;

import javax.xml.crypto.dsig.spec.ExcC14NParameterSpec;

import jdk.nashorn.internal.objects.DataPropertyDescriptor;
public class SeqList {
	Scanner scan=new Scanner(System.in);
	private int maxn=100;
	private int n=-1;
	private Object[] data;
	
	public void initate(){
		data=new Object[maxn];
		n=0;
		System.out.print("初始化完毕");
		}
	
	public void displayData(){
		if(n<1){
			System.out.println("线性表无数据");
			}else{
				for(int i=1;i<=n;i++){
					System.out.print(data[i]+" ");
			}
		}
	}
	
	public int getSize(){
		return n;
	}
	
	public void add(Object obj)throws Exception{
		if(n==-1){
			throw new Exception("未初始化");
		}
		if(n==maxn){
			throw new Exception("已满");
		}
		data[n+1]=obj;
		n++;
	}
	
	public void insert()throws Exception{
		System.out.print("请输入要插入第几个数据后面：");
		int i=scan.nextInt();
		if(i<0||i>n){
			throw new Exception("位置错误，请确定插入位置");
		}
		if(n==maxn){
			throw new Exception("已满");
		}
		System.out.println("请输入数据：");
		Object obj=scan.next();
		for(int j=n;j>i;j--){
			data[j+1]=obj;
			n++;
		}
	}
	public Object delete(int i)throws Exception{
		Object it=data[i];
		if(i<0||i>n){
			throw new Exception("位置错误，请确定插入位置");
		}
		for(int j=i;j<n;j++){
			data[j]=data[j+1];
		}
		n--;
		return it;
	}
	public Object getData() throws Exception{
		System.out.print("请输入你要查询的第几个数");
		int i=scan.nextInt();
		if(i<0||i>n){
			throw new Exception("无数据");
		}
		System.out.print("你要查找的数据是："+data[i]);
		return data[i];
	}
	public void updataData(){
		System.out.print("请输入你要修改的第几个数");
		int i=scan.nextInt();
		if(i<=0||i>n){
			return;
		}
		System.out.print("请输入修改的数据为：");
		Object obj=scan.next();
		data[i]=obj;
	}
}

T2:操作菜单

package ch2;

import java.util.Scanner;
public class SeqListMain {
	public static void main(String []args){
		SeqList seqlist=new SeqList();
		   Scanner scan=new Scanner(System.in);
		   int select;
		   do{
			   System.out.println("-----operation------");
			   System.out.println("1.初始化");
			   System.out.println("2.显示线性表数据");
			   System.out.println("3.求线性表数据个数");
			   System.out.println("4.追加数据");
			   System.out.println("5.插入数据");
			   System.out.println("6.删除数据");
			   System.out.println("7.查找数据");
			   System.out.println("8.修改数据");
			   System.out.println("9.退出
");
			   System.out.println("请输入：");
			   select=scan.nextInt();
			   switch(select){
			   case 1:
				   seqlist.initate();
				   break;
			   case 2:
				   seqlist.displayData();
				   break;
			   case 3:
				   if(seqlist.getSize()==0){
					   System.out.print("线性表空");
				   }else{
					   System.out.print("元素的个数是：");
					   System.out.print(seqlist.getSize());
				   };
				   break;
			   case 4:
				   System.out.print("请输入要加入的数据：");
				   Object obj=scan.next();
				   try{
					   seqlist.add(obj);
				   }catch (Exception e) {
					   System.out.print(e.toString());
					// TODO: handle exception
				}
				   break;
			   case 5:
				   try{
					   seqlist.insert();
				   }catch (Exception e) {
					   System.out.print(e.toString());
					// TODO: handle exception
				}
				   break;
			   case 6:
				   System.out.println("请输入你要删除第几个数：");
				   int i=scan.nextInt();
				   if(seqlist.getSize()==0){
					   System.out.print("表空");
				   }
				   if(i<0||i>seqlist.getSize()){
						System.out.print("位置错误，请确定插入位置");
					}
				   try{
					   seqlist.delete(i);
				   }catch (Exception e) {
					   System.out.print(e.toString());
					// TODO: handle exception
				}
				   break;
			   case 7:
				   try{
					   seqlist.getData();
				   }catch (Exception e) {
					   System.out.print(e.toString());
					// TODO: handle exception
				}
				   break;
			   case 8:
				   int number=0;
				   int index=0;
				   seqlist.updataData();
				   break;
			   case 9:
				   System.out.print("正在退出");
				   System.exit(0);break;
			   }
		   }while(true);
	}
}

4：Java的基本数据结构类

Collection

├List

│├LinkedList

│├ArrayList

│└Vector

│　└Stack

└Set

Map

├Hashtable

├HashMap

└WeakHashMap