栈(数组实现)

数组代码实现:

package com.ws;


public class ArrayStack {
    //栈的最大空间
    private int maxTop;
    private int stack[];
    private int top;
    private int bottom;
    //构造器
    public ArrayStack(int maxTop) {
        this.maxTop = maxTop;
        stack = new int[maxTop];
        top = -1;
        bottom = -1;
    }

    /**
     * 判断栈是否已满
     * @return true 满 ； false 没满
     */
    public boolean isFull() {
        if (top == maxTop - 1) {
            return true;
        }
        return false;
    }

    /**
     * 判断栈是否为空
     * @return true 空 ； false 没空
     */
    public boolean isEmpty() {
        if (top == bottom) {
            return true;
        }
        return false;
    }

    /**
     * 入栈
     * @param num
     */
    public void push(int num) {
        if (isFull()) {
            System.out.println("栈已满 无法入栈~");
            return;
        }
        stack[++top] = num;
    }

    /**
     * 出栈
     * @return
     */
    public int pop() {
        if (isEmpty()) {
            throw new RuntimeException("栈已空 无法出栈~");
        }
        return stack[top--];
    }

    /**
     * 遍历栈
     */
    public void showStack() {
        if (isEmpty()) {
            throw new RuntimeException("栈已空 无法出栈~");
        }
        int temp = top;
        while (true) {
            if (temp == -1) {
                break;
            }
            System.out.print(stack[temp--] + "  ");
        }
        System.out.println();
    }


}

测试代码:

package com.ws;

import java.util.Scanner;

public class Test1 {
    public static void main(String[] args) {
        ArrayStack stack = new ArrayStack(5);

        //接受输入按键
        char key = ' ';
        Scanner scanner = new Scanner(System.in);
        boolean loop = true;
        while(loop) {
            System.out.println("s(show):遍历栈");
            System.out.println("i(push): 入栈");
            System.out.println("o(pop): 出栈");
            System.out.println("e(exit): 退出");
            key = scanner.next().charAt(0);

            switch (key) {
                case 's':
                    try {
                        stack.showStack();
                    } catch (Exception e) {
                        System.out.println(e.getMessage());
                    }
                    break;
                case 'i':
                    System.out.println("请输入入栈数据:");
                    stack.push(scanner.nextInt());
                    break;
                case 'o':
                    try {
                        int num = stack.pop();
                        System.out.println("出栈数据为" + num);
                    } catch (Exception e) {
                        System.out.println(e.getMessage());
                    }
                    break;
                case 'e':
                    loop = false;
                    break;

                default:
                    break;
            }
        }
        System.out.println("程序退出~~~");

    
    }
}