数据结构之数组模拟栈

栈的特点即先进后出,采用数组模拟栈,实现栈的这一特性主要是靠定义一个指针(索引).

指针的初始位置指向的是-1

以下给出代码:

package com.ebiz.stack;

/**
 * @author YHj
 * @create 2019-07-20 14:20
 * 数组模拟栈
 */

public class ArrayStack {

    private  int maxSize;
    private  int [] arr;  //数组模拟栈
    private  int top = -1;

    //构造方法,初始化数组
    public ArrayStack(int maxSize) {
        this.maxSize=maxSize;
        this.arr = new int[maxSize];
    }

    //验证栈满
    public boolean isFull(){
        return top == maxSize-1;
    }

    //验证为空
    public boolean isEmpty(){
        return top == -1;
    }

    //入栈
    public void push(int value){
        if (isFull()){
            System.out.println("栈已满");
            return;
        }
        top++;
        arr[top]=value;
    }

    //出栈
    public int pop(){
        if(isEmpty()){
            throw new RuntimeException("栈已空");
        }
        int value=arr[top];
        top--;
        return value;
    }

    //遍历栈
    public void list(){
        if (isEmpty()){
            throw new RuntimeException("栈为空");
        }
        while (true){
            if (isEmpty()){
                System.out.println("栈为空");
                break;
            }
            System.out.printf("出站元素为%d%n",arr[top]);
            top--;
        }
    }
}

数组模拟栈,给出了pop,push,list几个简单方法,下面给出测试类,

package com.ebiz.stack;

/**
 * @author YHj
 * @create 2019-07-20 15:11
 */
public class Test {

    public static void main(String[] args) {

        //初始化栈
        ArrayStack stack = new ArrayStack(5);

        //添加元素
        for (int i = 1; i <=5 ; i++) {
            stack.push(i);
        }

        //获取栈顶
        System.out.println(stack.pop());
        System.out.println(stack.pop());

        //遍历栈
        stack.list();

    }
}