Java 3:顺序表的操作

标签：丢失   初始化   size   ensure   public   strong   private   查找   意思   

import java.util.Arrays;
public class SeqList1{
    private int[] array;
    private int size;
    //1.初始化,构造函数
    public  SeqList1(){
        array=new int[11];
        size=0;
    }
    //2.头插
    public void pushFront(int element){
        ensureCapacity();
        for(int i=size-1;i>=0;i--){// i代表的数据元素的下标，从后往前移动
            array[i+1]=array[i];
        }
        array[0]=element;
        size++;
    }
    //3.尾插
    public void pushBack(int element){
        ensureCapacity();
        array[size++]=element;
    }

    //4.中间插 
    public void insert(int index,int element){
        if(index<0||index>size){
            System.out.println("下标异常，不能插入");
        }
        ensureCapacity();
        for(int i=size;i>=index;i--){
            array[i+1]=array[i];
        }
        array[index]=element;
        size++;
    }

    //5.头删
    public void popFront(){
        if(size==0){
        System.out.println("空表");
        }
        for(int i=0;i<size;i++){
            array[i]=array[i+1];
        }
        size--;
    }

    //6.尾删
    public void popBack(){
        if(size==0){
    System.out.println("空表");
        }
    size--;}
    //7.中间删
    public void erase(int index){
        if(index<0||index>=size){
            System.out.println("下标异常,不能删除");
        }
        for(int i=index;i<size;i++){
            array[i]=array[i+1];
        }
        size--;
    }

    //8.查找
    public int indexOf(int element){
        for(int i=0;i<size;i++){
            if(array[i]==element){
                return i;
            }
        }
            return -1;
    }
    //9.根据下标，获取元素
    public int get(int index){
    if(index<0||index>=size){
        System.out.println("下标异常");
    }
    for(int i=0;i<size;i++){
        if(array[i]==array[index]){
            return array[i];
        }
    }
            return -1;
}

    //10.给定下标，修改元素的值
    public void set(int index,int element){
        for(int i=0;i<size;i++){
            if(i==index){
                array[i]=element;
            }
        }
    }
    //11.显示当前表中元素长度
    public int size(){
        return size;
    }
    //12.判断表是否为空
    public boolean isEmpty(){
        return size==0;
    }
    //13.查询表的容量
    public int capacity(){
        return array.length;
    }
    //14.打印显示表中已有元素
    public String toString(){
        return Arrays.toString(
        Arrays.copyOf(array,size));
    }
    //15.删除表中的一个元素
    public void remove(int element){
        int index=indexOf(element);
        if(index!=-1){
            erase(index);
        }
    }
    //16.删除表中相同元素
    public void removeAll(int element){
        int j=0;
        for(int i=0;i<size;i++){
            if(array[i]!=element){
                array[j++]=array[i];
            }
        }
        size=j;
    }
    //17.扩容
    private void ensureCapacity(){
        if(size<array.length){
            return ;
        }
        //申请空间
        int newCapacity=array.length+array.length/2;
        int[] newArray=new int[newCapacity];
       //搬家
       for(int i=0;i<array.length;i++){
           newArray[i]=array[i];
       }
       //官宣
       this.array=newArray;
}
    public static void test1(String [] args){
        SeqList1 sq = new SeqList1();
        //[]
        System.out.println(sq.toString());
        //头插1 2 3
        sq.pushFront(1);
        sq.pushFront(2);
        sq.pushFront(3);
        System.out.println(sq.toString());
        //尾插10，20，30
        sq.pushBack(10);
        sq.pushBack(20);
        sq.pushBack(30);
        System.out.println(sq.toString());
        //1,2,3,10,20,30
        sq.insert(2,15);
        sq.insert(4,28);
        System.out.println(sq.toString());
        //当前容量
        System.out.println(sq.capacity());
        //尾插

        sq.pushBack(10);
        sq.pushBack(2000);
        sq.pushBack(3000);
        // sq.pushBack(4000);
        sq.pushBack(5000);
        sq.pushBack(6000);
        System.out.println("当前容量为"+ sq.capacity());
        //头删
        sq.popFront();
        //尾删
        sq.popBack();
        //中间删
        sq.erase(3);
        System.out.println(sq.toString());
    }
        public static void test2(String [] args){
            SeqList1 s =new SeqList1();
        s.pushBack(1);
        s.pushBack(2);
        s.pushBack(3);
        s.pushBack(4);
        s.pushBack(1);
        s.pushBack(2);
        s.pushBack(3);
        s.pushBack(4);
        // [ 1, 2, 3, 4, 1, 2, 3, 4 ]
        System.out.println(s.toString());
        s.remove(4);
        // [ 1, 2, 3,  1, 2, 3, 4 ]
        System.out.println(s.toString());
        s.removeAll(4);
        // [ 1, 2, 3,  1, 2, 3,  ]
        System.out.println(s.toString());
        }
        public static void main(String[] args){
            test1(args);
            test2(args);
        }
    }

Java 3:顺序表的操作

标签：丢失   初始化   size   ensure   public   strong   private   查找   意思   

原文地址：https://blog.51cto.com/14234228/2403777