Stack的java实现

package structure;

import static net.mindview.util.Print.*;

import java.util.Arrays;
import java.util.Scanner;

/**
 * 栈的两种实现：数组和链表 ：arraylist 和 linkedlist
 * 本例实现的是数组的封装方式
 * @author Tom Tao
 *
 */

public class Stack {

    public static int[] num = new int[100];
    public static int top = 0;
    
    /*初始化*/
    public static void init(int n[]) {
        Arrays.fill(num, -1);
        for(int i = 1 ; n[i] != -1 ; i ++) {
            num[i] = n[i];
        }
    }
    
    /*打印*/
    public static void printStack() {
        for(int i = top ; i > 0 ; i --) {
            printnb(num[i] + " ");
        }
        print();
    }
    
    /*入栈*/
    public static void insert(int val) {
        num[++ top] = val;
        printStack();
    }
    
    /*获取栈顶*/
    public static int getTop() {
        return num[top];
    }
    
    /*出栈*/
    public static int pop() {
        int n = num[top];
        num[top --] = -1;
        return n;
    }
    
    /*判断是否为空*/
    public static boolean isEmpty() {
        return top <= 0;
    }
    
    /*test*/
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n[] = new int[100];
        Arrays.fill(n, -1);
        int val;
        print("please input the nums to init");
        while((val = sc.nextInt()) != -1){
            n[++ top] = val;
        }
        init(n);
        printStack();
        print("please input the num to insert");
        val = sc.nextInt();
        insert(val);
        print("get the top");
        print(getTop());
        print("pop");
        print(pop());
        printStack();
        print("is empty");
        print(isEmpty());
        sc.close();
    }
    
}