package cn.mrlij.stack;
 
import java.util.Arrays;
import java.util.Scanner;
 
/**
 * 使用數(shù)組實(shí)現(xiàn)棧
 * 
 * @author dreamer
 *
 */
public class ArrayStackDemo {
 public static void main(String[] args) {
 // 測試
 ArrayStack a = new ArrayStack(5);
 boolean flag = true;// 用于判斷循環(huán)結(jié)束的標(biāo)志
 Scanner sc = new Scanner(System.in);
 String key = "";// 用于接受菜單的選項(xiàng)
 while (flag) {
 System.out.println("show：顯示棧");
 System.out.println("exit：退出程序");
 System.out.println("push：進(jìn)棧");
 System.out.println("pop：出棧");
 key = sc.nextLine();
 switch (key) {
 case "show":
 a.show();
 break;
 case "exit":
 flag = false;
 System.out.println("程序結(jié)束！");
 break;
 
 case "push":
 
 System.out.println("請輸入要進(jìn)棧的數(shù)據(jù)：");
 int val = sc.nextInt();
 a.push(val);
 
 break;
 case "pop":
 try {
 int pop = a.pop();
 System.out.println("出棧的值是：" + pop);
 } catch (Exception e) {
 // TODO: handle exception
 System.out.println(e.getMessage());
 }
 break;
 default:
 break;
 }
 
 }
 
 }
}
 
class ArrayStack {
 private int MaxSize;// 定義數(shù)組的最大長度
 private int[] arr;// 定義數(shù)組，數(shù)據(jù)就放在該數(shù)組
 private int top = -1;// 定義棧頂，初始化數(shù)據(jù)為-1
 
 public ArrayStack(int maxSize) {
 this.MaxSize = maxSize;
 arr = new int[MaxSize];
 }
 
 // 判斷數(shù)組是否為空
 public boolean isEmpty() {
 
 return top == -1;
 }
 
 // 判斷數(shù)組是否滿了
 public boolean isFull() {
 System.out.println("棧頂：" + top + "最大長度：" + MaxSize);
 return top == MaxSize - 1;
 }
 
 // 進(jìn)棧
 public void push(int val) {
 // 先判斷棧是否滿了，滿了就不能添加進(jìn)去
 if (isFull()) {
 System.out.println("棧已經(jīng)滿了~~");
 return;
 }
 top++;
 arr[top] = val;
 }
 
 // 出棧
 public int pop() {
 // 先判斷棧是否為空
 if (isEmpty()) {
 throw new RuntimeException("棧為空，無法出棧！");
 }
 int val = arr[top];
 top--;
 return val;
 }
 
 public void show() {
 if (isEmpty()) {
 System.out.println("沒有數(shù)據(jù)");
 return;
 }
 for (int i = top; i >= 0; i--) {
 System.out.print(arr[i] + "\t");
 }
 System.out.println();
 }
 
}